diff --git a/.vortex/docs/content/development/composer.mdx b/.vortex/docs/content/development/composer.mdx
index 201c255208..0edaae6e46 100644
--- a/.vortex/docs/content/development/composer.mdx
+++ b/.vortex/docs/content/development/composer.mdx
@@ -554,6 +554,7 @@ where each module is installed.
 | [`drupal/devel`](https://www.drupal.org/project/devel) | A suite of development tools for inspecting variables, entities and the service container while debugging. | [Settings](settings.mdx#per-module-overrides) |
 | [`drupal/drupal_helpers`](https://www.drupal.org/project/drupal_helpers) | A collection of helper functions that simplify writing update hooks and deployment operations. | [Drupal helpers](modules/drupal-helpers.mdx) |
 | [`drupal/environment_indicator`](https://www.drupal.org/project/environment_indicator) | Shows a colored banner identifying the current environment to prevent accidental changes on the wrong site. | [Settings](settings.mdx#per-module-overrides) |
+| [`drupal/fast_404`](https://www.drupal.org/project/fast_404) | Answers requests for missing files with a 404 before Drupal bootstraps, saving the bootstrap that core's own fast 404 still performs. | [Settings](settings.mdx#per-module-overrides) |
 | [`drupal/generated_content`](https://www.drupal.org/project/generated_content) | Generates deterministic placeholder content from declarative definitions for development and testing. | [Generated content](modules/generated-content.mdx), [Settings](settings.mdx#per-module-overrides) |
 | [`drupal/migrate_plus`](https://www.drupal.org/project/migrate_plus) | Extends the core Migrate API with extra source and process plugins and configuration-entity migrations. | [Migrations](migrations.mdx) |
 | [`drupal/migrate_tools`](https://www.drupal.org/project/migrate_tools) | Provides Drush commands and a UI to run, roll back and monitor migrations. | [Migrations](migrations.mdx) |
diff --git a/.vortex/docs/content/development/modules/contributed-modules.mdx b/.vortex/docs/content/development/modules/contributed-modules.mdx
index ad7f8a5a61..6c1b1a46bf 100644
--- a/.vortex/docs/content/development/modules/contributed-modules.mdx
+++ b/.vortex/docs/content/development/modules/contributed-modules.mdx
@@ -77,6 +77,16 @@ No settings override.
 
 [`settings.environment_indicator.php`](https://github.com/drevops/vortex/blob/main/web/sites/default/includes/modules/settings.environment_indicator.php) names the indicator after the detected environment and colors it per environment - red for production, yellow for stage, green for dev - with the toolbar integration and favicon marker turned on.
 
+## Fast 404
+
+[Fast 404](https://www.drupal.org/project/fast_404) answers requests for missing files without bootstrapping Drupal. Drupal core already returns a lightweight 404 for the same file extensions, but only after a full bootstrap, so on a site serving many such requests the saving is the bootstrap itself.
+
+- **Installed:** Never enabled as a Drupal module. The handler runs from the settings file during the settings load, before the module system exists, so requiring the package is all that is needed.
+
+### Configuration
+
+[`settings.fast_404.php`](https://github.com/drevops/vortex/blob/main/web/sites/default/includes/modules/settings.fast_404.php) sets the file extensions to intercept, whitelists the front controller and the other entry-point scripts, allows anonymous access to image style derivatives, and calls `fast404_preboot()` with those settings.
+
 ## Generated Content
 
 [Generated content](https://www.drupal.org/project/generated_content) generates deterministic placeholder content from declarative definitions for development and testing.
diff --git a/.vortex/docs/cspell.json b/.vortex/docs/cspell.json
index 3ed389df31..047eb52088 100644
--- a/.vortex/docs/cspell.json
+++ b/.vortex/docs/cspell.json
@@ -75,6 +75,7 @@
         "phpcompatibility",
         "phpspec",
         "phpstorm",
+        "preboot",
         "pyrech",
         "redis",
         "renovatebot",
diff --git a/.vortex/installer/src/Prompts/Handlers/Modules.php b/.vortex/installer/src/Prompts/Handlers/Modules.php
index 053508946f..01b1fd785a 100644
--- a/.vortex/installer/src/Prompts/Handlers/Modules.php
+++ b/.vortex/installer/src/Prompts/Handlers/Modules.php
@@ -159,6 +159,7 @@ public static function getAvailableModules(): array {
       'devel' => 'Devel',
       'drupal_helpers' => 'Drupal helpers',
       'environment_indicator' => 'Environment indicator',
+      'fast_404' => 'Fast 404',
       'generated_content' => 'Generated content',
       'navigation_extra_tools' => 'Navigation extra tools',
       'pathauto' => 'Pathauto',
diff --git a/.vortex/installer/tests/Fixtures/handler_process/_baseline/composer.json b/.vortex/installer/tests/Fixtures/handler_process/_baseline/composer.json
index 72bcb955bb..f7f7db3224 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/_baseline/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/_baseline/composer.json
@@ -17,6 +17,7 @@
         "drupal/devel": "__VERSION__",
         "drupal/drupal_helpers": "__VERSION__",
         "drupal/environment_indicator": "__VERSION__",
+        "drupal/fast_404": "__VERSION__",
         "drupal/generated_content": "__VERSION__",
         "drupal/navigation_extra_tools": "__VERSION__",
         "drupal/pathauto": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index b1257d3531..7a2cbd0307 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -96,6 +96,17 @@ public function testEnvironmentNoOverrides(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_SUT;
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -109,6 +120,7 @@ public function testEnvironmentNoOverrides(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -181,6 +193,17 @@ public function testEnvironmentOverrides(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_SUT;
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
     $settings['file_public_path'] = 'custom_public';
     $settings['file_private_path'] = 'custom_private';
     $settings['file_temp_path'] = 'custom_temp';
@@ -238,6 +261,17 @@ public function testEnvironmentLocal(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_LOCAL;
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -252,6 +286,7 @@ public function testEnvironmentLocal(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -296,6 +331,17 @@ public function testEnvironmentLocalContainer(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_LOCAL;
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -312,6 +358,7 @@ public function testEnvironmentLocalContainer(): void {
       '^example\-site\.docker\.amazee\.io$',
       '^nginx$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -397,6 +444,17 @@ public function testEnvironmentGha(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_CI;
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -411,6 +469,7 @@ public function testEnvironmentGha(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
 
diff --git a/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/SettingsTestCase.php b/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/SettingsTestCase.php
index bafacd49e9..55db30e37a 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/SettingsTestCase.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/SettingsTestCase.php
@@ -209,6 +209,47 @@ protected function requireSettingsFile(array $pre_settings = [], array $pre_conf
     $this->databases = $databases;
   }
 
+  /**
+   * Require a per-module settings file with an explicit contrib path.
+   *
+   * Per-module settings files guarded by the presence of a module directory
+   * are unreachable through the site's own contrib path when the module is not
+   * required by the project.
+   *
+   * @param string $module
+   *   Module name as it appears in the `settings.<module>.php` file name.
+   * @param string $contrib_path
+   *   Path to the contrib modules directory to expose to the settings file.
+   * @param array $pre_settings
+   *   Array of settings to pre-populate.
+   * @param array $pre_config
+   *   Array of configs to pre-populate.
+   */
+  protected function requireModuleSettingsFile(string $module, string $contrib_path, array $pre_settings = [], array $pre_config = []): void {
+    $app_root = getcwd() . '/web';
+
+    if (!file_exists($app_root)) {
+      throw new \RuntimeException('Could not determine application root.');
+    }
+
+    $site_path = 'sites/default';
+    $file = implode(DIRECTORY_SEPARATOR, [$app_root, $site_path, 'includes', 'modules', sprintf('settings.%s.php', $module)]);
+
+    if (!file_exists($file)) {
+      throw new \RuntimeException(sprintf('Settings file %s does not exist.', $file));
+    }
+
+    $config = $pre_config;
+    $settings = $pre_settings;
+
+    require $file;
+
+    $this->app_root = $app_root;
+    $this->site_path = $site_path;
+    $this->config = $config;
+    $this->settings = $settings;
+  }
+
   /**
    * Assert that config retrieved from the real settings file match test data.
    *
diff --git a/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 8ac357bc5c..68c5f5b924 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/_baseline/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -4,6 +4,8 @@
 
 namespace Drupal;
 
+use PHPUnit\Framework\Attributes\PreserveGlobalState;
+use PHPUnit\Framework\Attributes\RunInSeparateProcess;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\Group;
 
@@ -19,6 +21,22 @@
 #[Group('drupal_settings')]
 class SwitchableSettingsTest extends SettingsTestCase {
 
+  /**
+   * Path to the contrib modules directory fixture.
+   */
+  protected ?string $contribFixture = NULL;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function tearDown(): void {
+    if (!is_null($this->contribFixture)) {
+      $this->removeContribFixture($this->contribFixture);
+    }
+
+    parent::tearDown();
+  }
+
   /**
    * Test ClamAV configs in Daemon mode with defaults.
    */
@@ -223,6 +241,103 @@ public static function dataProviderEnvironmentIndicator(): \Iterator {
     ];
   }
 
+  /**
+   * Test Fast 404 settings.
+   *
+   * Runs isolated so that the module stub owns the 'fast404_preboot()'
+   * declaration and its invocation marker is conclusive.
+   */
+  #[DataProvider('dataProviderFast404')]
+  #[RunInSeparateProcess]
+  #[PreserveGlobalState(FALSE)]
+  public function testFast404(bool $module_installed, array $expected_present, array $expected_absent = []): void {
+    $contrib_path = $this->createContribFixture($module_installed);
+
+    $this->requireModuleSettingsFile('fast_404', $contrib_path);
+
+    $this->assertSettingsContains($expected_present);
+    $this->assertSettingsNotContains($expected_absent);
+    $this->assertSame($module_installed, file_exists($contrib_path . '/fast_404/preboot'), 'Preboot invocation');
+  }
+
+  /**
+   * Data provider for testFast404().
+   */
+  public static function dataProviderFast404(): \Iterator {
+    yield 'module installed' => [
+      TRUE,
+      [
+        'fast404_exts' => '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i',
+        'fast404_allow_anon_imagecache' => TRUE,
+        'fast404_whitelist' => ['index.php', 'rss.xml', 'install.php', 'cron.php', 'update.php', 'xmlrpc.php'],
+        'fast404_html' => '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>',
+      ],
+    ];
+    yield 'module not installed' => [
+      FALSE,
+      [],
+      [
+        'fast404_exts' => NULL,
+        'fast404_allow_anon_imagecache' => NULL,
+        'fast404_whitelist' => NULL,
+        'fast404_html' => NULL,
+      ],
+    ];
+  }
+
+  /**
+   * Create a contrib modules directory fixture.
+   *
+   * The Fast 404 module is not required by the project, so its settings file
+   * guard can only be satisfied by a stub.
+   *
+   * @param bool $with_fast404
+   *   Create a stub of the Fast 404 module within the fixture. The stub marks
+   *   the directory when its preboot function is called.
+   *
+   * @return string
+   *   Path to the contrib modules directory fixture.
+   */
+  protected function createContribFixture(bool $with_fast404): string {
+    $this->contribFixture = getcwd() . '/.artifacts/tmp/' . uniqid('contrib-');
+
+    mkdir($this->contribFixture, 0777, TRUE);
+
+    if ($with_fast404) {
+      $stub = <<<'PHP'
+        <?php
+
+        function fast404_preboot(array $settings = []): void {
+          touch(__DIR__ . '/preboot');
+        }
+
+        PHP;
+
+      mkdir($this->contribFixture . '/fast_404');
+      file_put_contents($this->contribFixture . '/fast_404/fast404.inc', $stub);
+    }
+
+    return $this->contribFixture;
+  }
+
+  /**
+   * Remove the contrib modules directory fixture.
+   *
+   * @param string $path
+   *   Path to the contrib modules directory fixture.
+   */
+  protected function removeContribFixture(string $path): void {
+    foreach (glob($path . '/*/*') ?: [] as $file) {
+      unlink($file);
+    }
+
+    foreach (glob($path . '/*', GLOB_ONLYDIR) ?: [] as $dir) {
+      rmdir($dir);
+    }
+
+    rmdir($path);
+  }
+
   /**
    * Test Redis settings.
    */
diff --git a/.vortex/installer/tests/Fixtures/handler_process/_baseline/web/sites/default/includes/modules/settings.fast404.php b/.vortex/installer/tests/Fixtures/handler_process/_baseline/web/sites/default/includes/modules/settings.fast_404.php
similarity index 65%
rename from .vortex/installer/tests/Fixtures/handler_process/_baseline/web/sites/default/includes/modules/settings.fast404.php
rename to .vortex/installer/tests/Fixtures/handler_process/_baseline/web/sites/default/includes/modules/settings.fast_404.php
index 148f7d255f..d5fcf8950d 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/_baseline/web/sites/default/includes/modules/settings.fast404.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/_baseline/web/sites/default/includes/modules/settings.fast_404.php
@@ -7,9 +7,8 @@
 
 declare(strict_types=1);
 
-if (file_exists($contrib_path . '/fast404/fast404.inc')) {
-  // @codeCoverageIgnoreStart
-  $settings['fast404_exts'] = '/^(?!robots).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+if (file_exists($contrib_path . '/fast_404/fast404.inc')) {
+  $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
   $settings['fast404_allow_anon_imagecache'] = TRUE;
   $settings['fast404_whitelist'] = [
     'index.php',
@@ -19,10 +18,8 @@
     'update.php',
     'xmlrpc.php',
   ];
-  $settings['fast404_string_whitelisting'] = ['/advagg_'];
   $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
-  include_once $contrib_path . '/fast404/fast404.inc';
+  include_once $contrib_path . '/fast_404/fast404.inc';
   // @phpstan-ignore-next-line
   fast404_preboot($settings);
-  // @codeCoverageIgnoreEnd
 }
diff --git a/.vortex/installer/tests/Fixtures/handler_process/ciprovider_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/ciprovider_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/ciprovider_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/ciprovider_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/code_coverage_provider_codecov_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/code_coverage_provider_codecov_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/code_coverage_provider_codecov_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/code_coverage_provider_codecov_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/custom_modules_search_without_solr/composer.json b/.vortex/installer/tests/Fixtures/handler_process/custom_modules_search_without_solr/composer.json
index 856b514cc9..e602c50434 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/custom_modules_search_without_solr/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/custom_modules_search_without_solr/composer.json
@@ -1,4 +1,4 @@
-@@ -26,7 +26,6 @@
+@@ -27,7 +27,6 @@
          "drupal/robotstxt": "__VERSION__",
          "drupal/sdc_devel": "__VERSION__",
          "drupal/search_api": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/deploy_types_all_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/deploy_types_all_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/deploy_types_all_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/deploy_types_all_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/deploy_types_none_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/deploy_types_none_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/deploy_types_none_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/deploy_types_none_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/deps_updates_provider_ci_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/deps_updates_provider_ci_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/deps_updates_provider_ci_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/deps_updates_provider_ci_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/composer.json b/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/composer.json
index d64a8c52ce..5ea09f8f80 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/composer.json
@@ -1,4 +1,4 @@
-@@ -120,38 +120,38 @@
+@@ -121,38 +121,38 @@
                  "[web-root]/update.php": false
              },
              "locations": {
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/docroot/sites/default/includes/modules/settings.fast404.php b/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/docroot/sites/default/includes/modules/settings.fast_404.php
similarity index 65%
rename from .vortex/installer/tests/Fixtures/handler_process/hosting_acquia/docroot/sites/default/includes/modules/settings.fast404.php
rename to .vortex/installer/tests/Fixtures/handler_process/hosting_acquia/docroot/sites/default/includes/modules/settings.fast_404.php
index 148f7d255f..d5fcf8950d 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/docroot/sites/default/includes/modules/settings.fast404.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/docroot/sites/default/includes/modules/settings.fast_404.php
@@ -7,9 +7,8 @@
 
 declare(strict_types=1);
 
-if (file_exists($contrib_path . '/fast404/fast404.inc')) {
-  // @codeCoverageIgnoreStart
-  $settings['fast404_exts'] = '/^(?!robots).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+if (file_exists($contrib_path . '/fast_404/fast404.inc')) {
+  $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
   $settings['fast404_allow_anon_imagecache'] = TRUE;
   $settings['fast404_whitelist'] = [
     'index.php',
@@ -19,10 +18,8 @@
     'update.php',
     'xmlrpc.php',
   ];
-  $settings['fast404_string_whitelisting'] = ['/advagg_'];
   $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
-  include_once $contrib_path . '/fast404/fast404.inc';
+  include_once $contrib_path . '/fast_404/fast404.inc';
   // @phpstan-ignore-next-line
   fast404_preboot($settings);
-  // @codeCoverageIgnoreEnd
 }
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 1c24089541..e5274a0fa7 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -49,13 +49,14 @@
    }
  
    /**
-@@ -408,6 +452,337 @@
+@@ -466,6 +510,409 @@
      $settings['maintenance_theme'] = 'claro';
      $settings['skip_permissions_hardening'] = TRUE;
      $settings['config_sync_directory'] = '../config/default';
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -97,6 +98,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -110,6 +122,7 @@
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -151,6 +164,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -164,6 +188,7 @@
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -205,6 +230,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_STAGE;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -218,6 +254,7 @@
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -256,6 +293,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_PROD;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -269,6 +317,7 @@
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -312,6 +361,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -324,6 +384,7 @@
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -375,6 +436,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/tests/phpunit/Drupal/SettingsTestCase.php b/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/tests/phpunit/Drupal/SettingsTestCase.php
index 7823a4cb78..aad535a031 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/tests/phpunit/Drupal/SettingsTestCase.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/tests/phpunit/Drupal/SettingsTestCase.php
@@ -7,3 +7,12 @@ protected function requireSettingsFile(array $pre_settings = [], array $pre_conf
  
      if (!file_exists($app_root)) {
        throw new \RuntimeException('Could not determine application root.');
+@@ -226,7 +226,7 @@
+    *   Array of configs to pre-populate.
+    */
+   protected function requireModuleSettingsFile(string $module, string $contrib_path, array $pre_settings = [], array $pre_config = []): void {
+-    $app_root = getcwd() . '/web';
++    $app_root = getcwd() . '/docroot';
+ 
+     if (!file_exists($app_root)) {
+       throw new \RuntimeException('Could not determine application root.');
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/web/sites/default/includes/modules/-settings.fast404.php b/.vortex/installer/tests/Fixtures/handler_process/hosting_acquia/web/sites/default/includes/modules/-settings.fast_404.php
similarity index 100%
rename from .vortex/installer/tests/Fixtures/handler_process/hosting_acquia/web/sites/default/includes/modules/-settings.fast404.php
rename to .vortex/installer/tests/Fixtures/handler_process/hosting_acquia/web/sites/default/includes/modules/-settings.fast_404.php
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_lagoon/composer.json b/.vortex/installer/tests/Fixtures/handler_process/hosting_lagoon/composer.json
index 7813ec6268..0ef00bdaef 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_lagoon/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_lagoon/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,7 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,7 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/lagoon_logs": "__VERSION__",
          "drupal/navigation_extra_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/hosting_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index ab2ed9bfa4..7f3b316ae4 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -185,9 +185,9 @@
    }
  
    /**
-@@ -412,6 +592,287 @@
-       '^localhost$',
+@@ -471,6 +651,335 @@
      ];
+ 
      $this->assertSettings($settings);
 +  }
 +
@@ -235,6 +235,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -253,6 +264,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -300,6 +312,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -318,6 +341,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -365,6 +389,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_STAGE;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -383,6 +418,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -428,6 +464,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_PROD;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -446,6 +493,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/composer.json b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/composer.json
index d64a8c52ce..5ea09f8f80 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/composer.json
@@ -1,4 +1,4 @@
-@@ -120,38 +120,38 @@
+@@ -121,38 +121,38 @@
                  "[web-root]/update.php": false
              },
              "locations": {
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/docroot/sites/default/includes/modules/settings.fast404.php b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/docroot/sites/default/includes/modules/settings.fast_404.php
similarity index 65%
rename from .vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/docroot/sites/default/includes/modules/settings.fast404.php
rename to .vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/docroot/sites/default/includes/modules/settings.fast_404.php
index 148f7d255f..d5fcf8950d 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/docroot/sites/default/includes/modules/settings.fast404.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/docroot/sites/default/includes/modules/settings.fast_404.php
@@ -7,9 +7,8 @@
 
 declare(strict_types=1);
 
-if (file_exists($contrib_path . '/fast404/fast404.inc')) {
-  // @codeCoverageIgnoreStart
-  $settings['fast404_exts'] = '/^(?!robots).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+if (file_exists($contrib_path . '/fast_404/fast404.inc')) {
+  $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
   $settings['fast404_allow_anon_imagecache'] = TRUE;
   $settings['fast404_whitelist'] = [
     'index.php',
@@ -19,10 +18,8 @@
     'update.php',
     'xmlrpc.php',
   ];
-  $settings['fast404_string_whitelisting'] = ['/advagg_'];
   $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
-  include_once $contrib_path . '/fast404/fast404.inc';
+  include_once $contrib_path . '/fast_404/fast404.inc';
   // @phpstan-ignore-next-line
   fast404_preboot($settings);
-  // @codeCoverageIgnoreEnd
 }
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 1c24089541..e5274a0fa7 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -49,13 +49,14 @@
    }
  
    /**
-@@ -408,6 +452,337 @@
+@@ -466,6 +510,409 @@
      $settings['maintenance_theme'] = 'claro';
      $settings['skip_permissions_hardening'] = TRUE;
      $settings['config_sync_directory'] = '../config/default';
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -97,6 +98,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -110,6 +122,7 @@
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -151,6 +164,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -164,6 +188,7 @@
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -205,6 +230,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_STAGE;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -218,6 +254,7 @@
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -256,6 +293,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_PROD;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -269,6 +317,7 @@
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -312,6 +361,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -324,6 +384,7 @@
 +    $settings['trusted_host_patterns'] = [
 +      '^localhost$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -375,6 +436,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/tests/phpunit/Drupal/SettingsTestCase.php b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/tests/phpunit/Drupal/SettingsTestCase.php
index 7823a4cb78..aad535a031 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/tests/phpunit/Drupal/SettingsTestCase.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/tests/phpunit/Drupal/SettingsTestCase.php
@@ -7,3 +7,12 @@ protected function requireSettingsFile(array $pre_settings = [], array $pre_conf
  
      if (!file_exists($app_root)) {
        throw new \RuntimeException('Could not determine application root.');
+@@ -226,7 +226,7 @@
+    *   Array of configs to pre-populate.
+    */
+   protected function requireModuleSettingsFile(string $module, string $contrib_path, array $pre_settings = [], array $pre_config = []): void {
+-    $app_root = getcwd() . '/web';
++    $app_root = getcwd() . '/docroot';
+ 
+     if (!file_exists($app_root)) {
+       throw new \RuntimeException('Could not determine application root.');
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/web/sites/default/includes/modules/-settings.fast404.php b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/web/sites/default/includes/modules/-settings.fast_404.php
similarity index 100%
rename from .vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/web/sites/default/includes/modules/-settings.fast404.php
rename to .vortex/installer/tests/Fixtures/handler_process/hosting_project_name___acquia/web/sites/default/includes/modules/-settings.fast_404.php
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___lagoon/composer.json b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___lagoon/composer.json
index 7813ec6268..0ef00bdaef 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___lagoon/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___lagoon/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,7 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,7 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/lagoon_logs": "__VERSION__",
          "drupal/navigation_extra_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index ab2ed9bfa4..7f3b316ae4 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/hosting_project_name___lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -185,9 +185,9 @@
    }
  
    /**
-@@ -412,6 +592,287 @@
-       '^localhost$',
+@@ -471,6 +651,335 @@
      ];
+ 
      $this->assertSettings($settings);
 +  }
 +
@@ -235,6 +235,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -253,6 +264,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -300,6 +312,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -318,6 +341,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -365,6 +389,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_STAGE;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -383,6 +418,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -428,6 +464,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_PROD;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -446,6 +493,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_lagoon/composer.json b/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_lagoon/composer.json
index 7813ec6268..0ef00bdaef 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_lagoon/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_lagoon/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,7 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,7 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/lagoon_logs": "__VERSION__",
          "drupal/navigation_extra_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index ab2ed9bfa4..7f3b316ae4 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_disabled_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -185,9 +185,9 @@
    }
  
    /**
-@@ -412,6 +592,287 @@
-       '^localhost$',
+@@ -471,6 +651,335 @@
      ];
+ 
      $this->assertSettings($settings);
 +  }
 +
@@ -235,6 +235,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -253,6 +264,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -300,6 +312,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -318,6 +341,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -365,6 +389,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_STAGE;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -383,6 +418,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -428,6 +464,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_PROD;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -446,6 +493,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled/composer.json b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled/composer.json
index d97c45d6d7..0570175784 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,8 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,8 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/migrate_plus": "__VERSION__",
 +        "drupal/migrate_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index abc65393b3..b69ba73853 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -150,6 +150,13 @@
+@@ -162,6 +162,13 @@
      $databases['default']['default']['collation'] = 'utf8_general_ci';
      $databases['default']['default']['driver'] = 'mysql';
      $databases['default']['default']['prefix'] = '';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_circleci/composer.json b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_circleci/composer.json
index d97c45d6d7..0570175784 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_circleci/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_circleci/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,8 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,8 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/migrate_plus": "__VERSION__",
 +        "drupal/migrate_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 7046f6392e..d60a23a0d5 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -150,6 +150,13 @@
+@@ -162,6 +162,13 @@
      $databases['default']['default']['collation'] = 'utf8_general_ci';
      $databases['default']['default']['driver'] = 'mysql';
      $databases['default']['default']['prefix'] = '';
@@ -12,7 +12,7 @@
      $this->assertEquals($databases, $this->databases);
  
      // Verify key config overrides.
-@@ -356,9 +363,9 @@
+@@ -403,9 +410,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_lagoon/composer.json b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_lagoon/composer.json
index bfccd7b612..a75e30da0c 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_lagoon/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_lagoon/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,9 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,9 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/lagoon_logs": "__VERSION__",
 +        "drupal/migrate_plus": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 944368a963..e94dc38c7e 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_enabled_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -185,7 +185,7 @@
    }
  
    /**
-@@ -150,6 +330,13 @@
+@@ -162,6 +342,13 @@
      $databases['default']['default']['collation'] = 'utf8_general_ci';
      $databases['default']['default']['driver'] = 'mysql';
      $databases['default']['default']['prefix'] = '';
@@ -199,9 +199,9 @@
      $this->assertEquals($databases, $this->databases);
  
      // Verify key config overrides.
-@@ -412,6 +599,287 @@
-       '^localhost$',
+@@ -471,6 +658,335 @@
      ];
+ 
      $this->assertSettings($settings);
 +  }
 +
@@ -249,6 +249,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -267,6 +278,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -314,6 +326,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -332,6 +355,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -379,6 +403,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_STAGE;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -397,6 +432,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -442,6 +478,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_PROD;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -460,6 +507,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_acquia/composer.json b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_acquia/composer.json
index d97c45d6d7..0570175784 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_acquia/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_acquia/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,8 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,8 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/migrate_plus": "__VERSION__",
 +        "drupal/migrate_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index abc65393b3..b69ba73853 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_acquia/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -150,6 +150,13 @@
+@@ -162,6 +162,13 @@
      $databases['default']['default']['collation'] = 'utf8_general_ci';
      $databases['default']['default']['driver'] = 'mysql';
      $databases['default']['default']['prefix'] = '';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_container_registry/composer.json b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_container_registry/composer.json
index d97c45d6d7..0570175784 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_container_registry/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_container_registry/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,8 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,8 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/migrate_plus": "__VERSION__",
 +        "drupal/migrate_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_container_registry/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_container_registry/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index abc65393b3..b69ba73853 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_container_registry/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_container_registry/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -150,6 +150,13 @@
+@@ -162,6 +162,13 @@
      $databases['default']['default']['collation'] = 'utf8_general_ci';
      $databases['default']['default']['driver'] = 'mysql';
      $databases['default']['default']['prefix'] = '';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_ftp/composer.json b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_ftp/composer.json
index d97c45d6d7..0570175784 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_ftp/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_ftp/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,8 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,8 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/migrate_plus": "__VERSION__",
 +        "drupal/migrate_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_ftp/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_ftp/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index abc65393b3..b69ba73853 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_ftp/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_ftp/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -150,6 +150,13 @@
+@@ -162,6 +162,13 @@
      $databases['default']['default']['collation'] = 'utf8_general_ci';
      $databases['default']['default']['driver'] = 'mysql';
      $databases['default']['default']['prefix'] = '';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_lagoon/composer.json b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_lagoon/composer.json
index d97c45d6d7..0570175784 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_lagoon/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_lagoon/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,8 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,8 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/migrate_plus": "__VERSION__",
 +        "drupal/migrate_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index abc65393b3..b69ba73853 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -150,6 +150,13 @@
+@@ -162,6 +162,13 @@
      $databases['default']['default']['collation'] = 'utf8_general_ci';
      $databases['default']['default']['driver'] = 'mysql';
      $databases['default']['default']['prefix'] = '';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_s3/composer.json b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_s3/composer.json
index d97c45d6d7..0570175784 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_s3/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_s3/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,8 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,8 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/migrate_plus": "__VERSION__",
 +        "drupal/migrate_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_s3/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_s3/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index abc65393b3..b69ba73853 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_s3/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_s3/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -150,6 +150,13 @@
+@@ -162,6 +162,13 @@
      $databases['default']['default']['collation'] = 'utf8_general_ci';
      $databases['default']['default']['driver'] = 'mysql';
      $databases['default']['default']['prefix'] = '';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_url/composer.json b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_url/composer.json
index d97c45d6d7..0570175784 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_url/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_url/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,8 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,8 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/migrate_plus": "__VERSION__",
 +        "drupal/migrate_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_url/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_url/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index abc65393b3..b69ba73853 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_url/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/migration_fetch_source_url/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -150,6 +150,13 @@
+@@ -162,6 +162,13 @@
      $databases['default']['default']['collation'] = 'utf8_general_ci';
      $databases['default']['default']['driver'] = 'mysql';
      $databases['default']['default']['prefix'] = '';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_config_split/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_config_split/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 428a92b501..7d04460926 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_config_split/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_config_split/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -208,7 +208,6 @@
+@@ -231,7 +231,6 @@
      $this->requireSettingsFile();
  
      $config['automated_cron.settings']['interval'] = 0;
@@ -6,7 +6,7 @@
      $config['environment_indicator.indicator']['bg_color'] = '#006600';
      $config['environment_indicator.indicator']['fg_color'] = '#ffffff';
      $config['environment_indicator.indicator']['name'] = self::ENVIRONMENT_LOCAL;
-@@ -266,7 +265,6 @@
+@@ -301,7 +300,6 @@
      $this->requireSettingsFile();
  
      $config['automated_cron.settings']['interval'] = 0;
@@ -14,7 +14,7 @@
      $config['environment_indicator.indicator']['bg_color'] = '#006600';
      $config['environment_indicator.indicator']['fg_color'] = '#ffffff';
      $config['environment_indicator.indicator']['name'] = self::ENVIRONMENT_LOCAL;
-@@ -366,7 +364,6 @@
+@@ -413,7 +411,6 @@
      $this->requireSettingsFile();
  
      $config['automated_cron.settings']['interval'] = 0;
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_config_split/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_config_split/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 476aa8044b..62759bede2 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_config_split/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_config_split/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -76,91 +76,6 @@
+@@ -94,91 +94,6 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel/composer.json
index 3bca73f682..3b9378f124 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel/composer.json
@@ -5,4 +5,4 @@
 -        "drupal/devel": "__VERSION__",
          "drupal/drupal_helpers": "__VERSION__",
          "drupal/environment_indicator": "__VERSION__",
-         "drupal/generated_content": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 3f691c0d4c..5fc93177d7 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -6,7 +6,7 @@
        'generated_content',
        'reroute_email',
        'sdc_devel',
-@@ -171,7 +170,6 @@
+@@ -183,7 +182,6 @@
      // Verify settings overrides.
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -14,7 +14,7 @@
        'generated_content',
        'reroute_email',
        'sdc_devel',
-@@ -229,7 +227,6 @@
+@@ -252,7 +250,6 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -22,7 +22,7 @@
        'generated_content',
        'reroute_email',
        'sdc_devel',
-@@ -287,7 +284,6 @@
+@@ -322,7 +319,6 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -30,7 +30,7 @@
        'generated_content',
        'reroute_email',
        'sdc_devel',
-@@ -388,7 +384,6 @@
+@@ -435,7 +431,6 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel/composer.json
index 3ed17cf052..4fceba9033 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel/composer.json
@@ -5,8 +5,8 @@
 -        "drupal/devel": "__VERSION__",
          "drupal/drupal_helpers": "__VERSION__",
          "drupal/environment_indicator": "__VERSION__",
-         "drupal/generated_content": "__VERSION__",
-@@ -24,7 +23,6 @@
+         "drupal/fast_404": "__VERSION__",
+@@ -25,7 +24,6 @@
          "drupal/redis": "__VERSION__",
          "drupal/reroute_email": "__VERSION__",
          "drupal/robotstxt": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index ba0a8bca0f..eb63880990 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -9,7 +9,7 @@
        'testmode',
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -171,10 +169,8 @@
+@@ -183,10 +181,8 @@
      // Verify settings overrides.
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -20,7 +20,7 @@
        'testmode',
      ];
      $settings['config_sync_directory'] = 'custom_config';
-@@ -229,10 +225,8 @@
+@@ -252,10 +248,8 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -31,7 +31,7 @@
        'testmode',
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -287,10 +281,8 @@
+@@ -322,10 +316,8 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -42,7 +42,7 @@
        'testmode',
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -388,10 +380,8 @@
+@@ -435,10 +427,8 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content/composer.json
index fd5c081c4f..10ae965ce0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content/composer.json
@@ -1,15 +1,16 @@
-@@ -14,10 +14,8 @@
+@@ -14,11 +14,9 @@
          "drupal/config_update": "__VERSION__",
          "drupal/core-composer-scaffold": "__VERSION__",
          "drupal/core-recommended": "__VERSION__",
 -        "drupal/devel": "__VERSION__",
          "drupal/drupal_helpers": "__VERSION__",
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
 -        "drupal/generated_content": "__VERSION__",
          "drupal/navigation_extra_tools": "__VERSION__",
          "drupal/pathauto": "__VERSION__",
          "drupal/redirect": "__VERSION__",
-@@ -24,7 +22,6 @@
+@@ -25,7 +23,6 @@
          "drupal/redis": "__VERSION__",
          "drupal/reroute_email": "__VERSION__",
          "drupal/robotstxt": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index b8792de6d6..65abdc4836 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -9,7 +9,7 @@
        'testmode',
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -171,10 +168,7 @@
+@@ -183,10 +180,7 @@
      // Verify settings overrides.
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -20,7 +20,7 @@
        'testmode',
      ];
      $settings['config_sync_directory'] = 'custom_config';
-@@ -229,10 +223,7 @@
+@@ -252,10 +246,7 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -31,7 +31,7 @@
        'testmode',
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -287,10 +278,7 @@
+@@ -322,10 +313,7 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -42,7 +42,7 @@
        'testmode',
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -388,10 +376,7 @@
+@@ -435,10 +423,7 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode/composer.json
index d185f9528d..e309bead75 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode/composer.json
@@ -1,15 +1,16 @@
-@@ -14,10 +14,8 @@
+@@ -14,11 +14,9 @@
          "drupal/config_update": "__VERSION__",
          "drupal/core-composer-scaffold": "__VERSION__",
          "drupal/core-recommended": "__VERSION__",
 -        "drupal/devel": "__VERSION__",
          "drupal/drupal_helpers": "__VERSION__",
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
 -        "drupal/generated_content": "__VERSION__",
          "drupal/navigation_extra_tools": "__VERSION__",
          "drupal/pathauto": "__VERSION__",
          "drupal/redirect": "__VERSION__",
-@@ -24,13 +22,11 @@
+@@ -25,13 +23,11 @@
          "drupal/redis": "__VERSION__",
          "drupal/reroute_email": "__VERSION__",
          "drupal/robotstxt": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 571a332dda..c744bfb511 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -10,7 +10,7 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -171,11 +167,7 @@
+@@ -183,11 +179,7 @@
      // Verify settings overrides.
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -22,7 +22,7 @@
      ];
      $settings['config_sync_directory'] = 'custom_config';
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -229,11 +221,7 @@
+@@ -252,11 +244,7 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -34,7 +34,7 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -287,11 +275,7 @@
+@@ -322,11 +310,7 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -46,7 +46,7 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -388,11 +372,7 @@
+@@ -435,11 +419,7 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/composer.json
index 0964463a7e..068eb5e285 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/composer.json
@@ -1,10 +1,11 @@
-@@ -14,23 +14,18 @@
+@@ -14,24 +14,19 @@
          "drupal/config_update": "__VERSION__",
          "drupal/core-composer-scaffold": "__VERSION__",
          "drupal/core-recommended": "__VERSION__",
 -        "drupal/devel": "__VERSION__",
          "drupal/drupal_helpers": "__VERSION__",
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
 -        "drupal/generated_content": "__VERSION__",
          "drupal/navigation_extra_tools": "__VERSION__",
          "drupal/pathauto": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 320c6e1ac9..61075c6d07 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -18,7 +18,7 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -162,9 +154,6 @@
+@@ -174,9 +166,6 @@
      $config['shield.settings']['shield_enable'] = TRUE;
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
@@ -28,7 +28,7 @@
      $config['system.performance']['cache']['page']['max_age'] = 1800;
      $this->assertConfig($config);
  
-@@ -171,11 +160,6 @@
+@@ -183,11 +172,6 @@
      // Verify settings overrides.
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -40,7 +40,7 @@
      ];
      $settings['config_sync_directory'] = 'custom_config';
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -220,9 +204,6 @@
+@@ -243,9 +227,6 @@
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['system.logging']['error_level'] = 'all';
      $config['system.performance']['cache']['page']['max_age'] = 900;
@@ -50,7 +50,7 @@
      $config['seckit.settings']['seckit_xss']['csp']['checkbox'] = FALSE;
      $config['seckit.settings']['seckit_xss']['csp']['upgrade-req'] = FALSE;
      $this->assertConfig($config);
-@@ -229,11 +210,6 @@
+@@ -252,11 +233,6 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -62,7 +62,7 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -278,9 +254,6 @@
+@@ -313,9 +289,6 @@
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['system.logging']['error_level'] = 'all';
      $config['system.performance']['cache']['page']['max_age'] = 900;
@@ -72,7 +72,7 @@
      $config['seckit.settings']['seckit_xss']['csp']['checkbox'] = FALSE;
      $config['seckit.settings']['seckit_xss']['csp']['upgrade-req'] = FALSE;
      $this->assertConfig($config);
-@@ -287,11 +260,6 @@
+@@ -322,11 +295,6 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -84,7 +84,7 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -379,9 +347,6 @@
+@@ -426,9 +394,6 @@
      $config['system.logging']['error_level'] = 'all';
      $config['system.mail']['interface']['default'] = 'test_mail_collector';
      $config['system.performance']['cache']['page']['max_age'] = 900;
@@ -94,7 +94,7 @@
      $config['seckit.settings']['seckit_xss']['csp']['checkbox'] = FALSE;
      $config['seckit.settings']['seckit_xss']['csp']['upgrade-req'] = FALSE;
      $this->assertConfig($config);
-@@ -388,11 +353,6 @@
+@@ -435,11 +400,6 @@
  
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 2c1705e3eb..371b43742b 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_devel_sdc_devel_generated_content_testmode_reroute_email/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -665,156 +665,6 @@
+@@ -780,156 +780,6 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_drupal_helpers/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_drupal_helpers/composer.json
index ef2d2be00f..3da9edf20b 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_drupal_helpers/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_drupal_helpers/composer.json
@@ -4,5 +4,5 @@
          "drupal/devel": "__VERSION__",
 -        "drupal/drupal_helpers": "__VERSION__",
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
-         "drupal/navigation_extra_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/composer.json
index 1daad799ee..6f8bf8b1df 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/composer.json
@@ -3,6 +3,6 @@
          "drupal/devel": "__VERSION__",
          "drupal/drupal_helpers": "__VERSION__",
 -        "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
          "drupal/navigation_extra_tools": "__VERSION__",
-         "drupal/pathauto": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index c2afc63476..053bb8fd13 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -10,7 +10,7 @@
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
      $config['shield.settings']['shield_enable'] = TRUE;
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
-@@ -153,11 +148,6 @@
+@@ -165,11 +160,6 @@
      $this->assertEquals($databases, $this->databases);
  
      // Verify key config overrides.
@@ -22,7 +22,7 @@
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
      $config['shield.settings']['shield_enable'] = TRUE;
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
-@@ -209,11 +199,6 @@
+@@ -232,11 +222,6 @@
  
      $config['automated_cron.settings']['interval'] = 0;
      $config['config_split.config_split.local']['status'] = TRUE;
@@ -34,7 +34,7 @@
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
      $config['shield.settings']['shield_enable'] = FALSE;
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
-@@ -267,11 +252,6 @@
+@@ -302,11 +287,6 @@
  
      $config['automated_cron.settings']['interval'] = 0;
      $config['config_split.config_split.local']['status'] = TRUE;
@@ -46,7 +46,7 @@
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
      $config['shield.settings']['shield_enable'] = FALSE;
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
-@@ -367,11 +347,6 @@
+@@ -414,11 +394,6 @@
  
      $config['automated_cron.settings']['interval'] = 0;
      $config['config_split.config_split.ci']['status'] = TRUE;
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 0c6765d951..040a9cf13f 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_environment_indicator/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -161,69 +161,6 @@
+@@ -179,69 +179,6 @@
    }
  
    /**
@@ -65,6 +65,6 @@
 -  }
 -
 -  /**
-    * Test Redis settings.
-    */
-   public function testRedis(): void {
+    * Test Fast 404 settings.
+    *
+    * Runs isolated so that the module stub owns the 'fast404_preboot()'
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_fast_404/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_fast_404/composer.json
new file mode 100644
index 0000000000..127ade0d18
--- /dev/null
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_fast_404/composer.json
@@ -0,0 +1,8 @@
+@@ -17,7 +17,6 @@
+         "drupal/devel": "__VERSION__",
+         "drupal/drupal_helpers": "__VERSION__",
+         "drupal/environment_indicator": "__VERSION__",
+-        "drupal/fast_404": "__VERSION__",
+         "drupal/generated_content": "__VERSION__",
+         "drupal/navigation_extra_tools": "__VERSION__",
+         "drupal/pathauto": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_fast_404/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_fast_404/tests/phpunit/Drupal/EnvironmentSettingsTest.php
new file mode 100644
index 0000000000..174b289948
--- /dev/null
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_fast_404/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -0,0 +1,90 @@
+@@ -96,17 +96,6 @@
+     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
+     $settings['entity_update_batch_size'] = 50;
+     $settings['environment'] = self::ENVIRONMENT_SUT;
+-    $settings['fast404_allow_anon_imagecache'] = TRUE;
+-    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+-    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+-    $settings['fast404_whitelist'] = [
+-      'index.php',
+-      'rss.xml',
+-      'install.php',
+-      'cron.php',
+-      'update.php',
+-      'xmlrpc.php',
+-    ];
+     $settings['file_public_path'] = 'sites/default/files';
+     $settings['file_private_path'] = 'sites/default/files/private';
+     $settings['file_temp_path'] = '/tmp';
+@@ -193,17 +182,6 @@
+     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
+     $settings['entity_update_batch_size'] = 50;
+     $settings['environment'] = self::ENVIRONMENT_SUT;
+-    $settings['fast404_allow_anon_imagecache'] = TRUE;
+-    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+-    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+-    $settings['fast404_whitelist'] = [
+-      'index.php',
+-      'rss.xml',
+-      'install.php',
+-      'cron.php',
+-      'update.php',
+-      'xmlrpc.php',
+-    ];
+     $settings['file_public_path'] = 'custom_public';
+     $settings['file_private_path'] = 'custom_private';
+     $settings['file_temp_path'] = 'custom_temp';
+@@ -261,17 +239,6 @@
+     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
+     $settings['entity_update_batch_size'] = 50;
+     $settings['environment'] = self::ENVIRONMENT_LOCAL;
+-    $settings['fast404_allow_anon_imagecache'] = TRUE;
+-    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+-    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+-    $settings['fast404_whitelist'] = [
+-      'index.php',
+-      'rss.xml',
+-      'install.php',
+-      'cron.php',
+-      'update.php',
+-      'xmlrpc.php',
+-    ];
+     $settings['file_public_path'] = 'sites/default/files';
+     $settings['file_private_path'] = 'sites/default/files/private';
+     $settings['file_temp_path'] = '/tmp';
+@@ -331,17 +298,6 @@
+     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
+     $settings['entity_update_batch_size'] = 50;
+     $settings['environment'] = self::ENVIRONMENT_LOCAL;
+-    $settings['fast404_allow_anon_imagecache'] = TRUE;
+-    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+-    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+-    $settings['fast404_whitelist'] = [
+-      'index.php',
+-      'rss.xml',
+-      'install.php',
+-      'cron.php',
+-      'update.php',
+-      'xmlrpc.php',
+-    ];
+     $settings['file_public_path'] = 'sites/default/files';
+     $settings['file_private_path'] = 'sites/default/files/private';
+     $settings['file_temp_path'] = '/tmp';
+@@ -444,17 +400,6 @@
+     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
+     $settings['entity_update_batch_size'] = 50;
+     $settings['environment'] = self::ENVIRONMENT_CI;
+-    $settings['fast404_allow_anon_imagecache'] = TRUE;
+-    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+-    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+-    $settings['fast404_whitelist'] = [
+-      'index.php',
+-      'rss.xml',
+-      'install.php',
+-      'cron.php',
+-      'update.php',
+-      'xmlrpc.php',
+-    ];
+     $settings['file_public_path'] = 'sites/default/files';
+     $settings['file_private_path'] = 'sites/default/files/private';
+     $settings['file_temp_path'] = '/tmp';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_fast_404/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_fast_404/tests/phpunit/Drupal/SwitchableSettingsTest.php
new file mode 100644
index 0000000000..62df4887ee
--- /dev/null
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_fast_404/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -0,0 +1,136 @@
+@@ -4,8 +4,6 @@
+ 
+ namespace Drupal;
+ 
+-use PHPUnit\Framework\Attributes\PreserveGlobalState;
+-use PHPUnit\Framework\Attributes\RunInSeparateProcess;
+ use PHPUnit\Framework\Attributes\DataProvider;
+ use PHPUnit\Framework\Attributes\Group;
+ 
+@@ -22,22 +20,6 @@
+ class SwitchableSettingsTest extends SettingsTestCase {
+ 
+   /**
+-   * Path to the contrib modules directory fixture.
+-   */
+-  protected ?string $contribFixture = NULL;
+-
+-  /**
+-   * {@inheritdoc}
+-   */
+-  protected function tearDown(): void {
+-    if (!is_null($this->contribFixture)) {
+-      $this->removeContribFixture($this->contribFixture);
+-    }
+-
+-    parent::tearDown();
+-  }
+-
+-  /**
+    * Test ClamAV configs in Daemon mode with defaults.
+    */
+   public function testClamavDaemonCustom(): void {
+@@ -239,103 +221,6 @@
+         'environment_indicator.settings' => ['toolbar_integration' => [TRUE], 'favicon' => TRUE],
+       ],
+     ];
+-  }
+-
+-  /**
+-   * Test Fast 404 settings.
+-   *
+-   * Runs isolated so that the module stub owns the 'fast404_preboot()'
+-   * declaration and its invocation marker is conclusive.
+-   */
+-  #[DataProvider('dataProviderFast404')]
+-  #[RunInSeparateProcess]
+-  #[PreserveGlobalState(FALSE)]
+-  public function testFast404(bool $module_installed, array $expected_present, array $expected_absent = []): void {
+-    $contrib_path = $this->createContribFixture($module_installed);
+-
+-    $this->requireModuleSettingsFile('fast_404', $contrib_path);
+-
+-    $this->assertSettingsContains($expected_present);
+-    $this->assertSettingsNotContains($expected_absent);
+-    $this->assertSame($module_installed, file_exists($contrib_path . '/fast_404/preboot'), 'Preboot invocation');
+-  }
+-
+-  /**
+-   * Data provider for testFast404().
+-   */
+-  public static function dataProviderFast404(): \Iterator {
+-    yield 'module installed' => [
+-      TRUE,
+-      [
+-        'fast404_exts' => '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i',
+-        'fast404_allow_anon_imagecache' => TRUE,
+-        'fast404_whitelist' => ['index.php', 'rss.xml', 'install.php', 'cron.php', 'update.php', 'xmlrpc.php'],
+-        'fast404_html' => '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>',
+-      ],
+-    ];
+-    yield 'module not installed' => [
+-      FALSE,
+-      [],
+-      [
+-        'fast404_exts' => NULL,
+-        'fast404_allow_anon_imagecache' => NULL,
+-        'fast404_whitelist' => NULL,
+-        'fast404_html' => NULL,
+-      ],
+-    ];
+-  }
+-
+-  /**
+-   * Create a contrib modules directory fixture.
+-   *
+-   * The Fast 404 module is not required by the project, so its settings file
+-   * guard can only be satisfied by a stub.
+-   *
+-   * @param bool $with_fast404
+-   *   Create a stub of the Fast 404 module within the fixture. The stub marks
+-   *   the directory when its preboot function is called.
+-   *
+-   * @return string
+-   *   Path to the contrib modules directory fixture.
+-   */
+-  protected function createContribFixture(bool $with_fast404): string {
+-    $this->contribFixture = getcwd() . '/.artifacts/tmp/' . uniqid('contrib-');
+-
+-    mkdir($this->contribFixture, 0777, TRUE);
+-
+-    if ($with_fast404) {
+-      $stub = <<<'PHP'
+-        <?php
+-
+-        function fast404_preboot(array $settings = []): void {
+-          touch(__DIR__ . '/preboot');
+-        }
+-
+-        PHP;
+-
+-      mkdir($this->contribFixture . '/fast_404');
+-      file_put_contents($this->contribFixture . '/fast_404/fast404.inc', $stub);
+-    }
+-
+-    return $this->contribFixture;
+-  }
+-
+-  /**
+-   * Remove the contrib modules directory fixture.
+-   *
+-   * @param string $path
+-   *   Path to the contrib modules directory fixture.
+-   */
+-  protected function removeContribFixture(string $path): void {
+-    foreach (glob($path . '/*/*') ?: [] as $file) {
+-      unlink($file);
+-    }
+-
+-    foreach (glob($path . '/*', GLOB_ONLYDIR) ?: [] as $dir) {
+-      rmdir($dir);
+-    }
+-
+-    rmdir($path);
+   }
+ 
+   /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_fast_404/web/sites/default/includes/modules/-settings.fast_404.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_fast_404/web/sites/default/includes/modules/-settings.fast_404.php
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_generated_content/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_generated_content/composer.json
index 5f04d5acef..b343647ade 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_generated_content/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_generated_content/composer.json
@@ -1,7 +1,7 @@
-@@ -17,7 +17,6 @@
-         "drupal/devel": "__VERSION__",
+@@ -18,7 +18,6 @@
          "drupal/drupal_helpers": "__VERSION__",
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
 -        "drupal/generated_content": "__VERSION__",
          "drupal/navigation_extra_tools": "__VERSION__",
          "drupal/pathauto": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_generated_content/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_generated_content/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 963432045b..a8c42046ec 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_generated_content/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_generated_content/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -6,7 +6,7 @@
        'reroute_email',
        'sdc_devel',
        'testmode',
-@@ -172,7 +171,6 @@
+@@ -184,7 +183,6 @@
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
        'devel',
@@ -14,7 +14,7 @@
        'reroute_email',
        'sdc_devel',
        'testmode',
-@@ -230,7 +228,6 @@
+@@ -253,7 +251,6 @@
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
        'devel',
@@ -22,7 +22,7 @@
        'reroute_email',
        'sdc_devel',
        'testmode',
-@@ -288,7 +285,6 @@
+@@ -323,7 +320,6 @@
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
        'devel',
@@ -30,7 +30,7 @@
        'reroute_email',
        'sdc_devel',
        'testmode',
-@@ -389,7 +385,6 @@
+@@ -436,7 +432,6 @@
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
        'devel',
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_navigation_extra_tools/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_navigation_extra_tools/composer.json
index dcf223d36a..090d1634f5 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_navigation_extra_tools/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_navigation_extra_tools/composer.json
@@ -1,6 +1,6 @@
-@@ -18,7 +18,6 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,7 +19,6 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 -        "drupal/navigation_extra_tools": "__VERSION__",
          "drupal/pathauto": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_pathauto/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_pathauto/composer.json
index 1486737001..adebd85642 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_pathauto/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_pathauto/composer.json
@@ -1,5 +1,5 @@
-@@ -19,7 +19,6 @@
-         "drupal/environment_indicator": "__VERSION__",
+@@ -20,7 +20,6 @@
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
          "drupal/navigation_extra_tools": "__VERSION__",
 -        "drupal/pathauto": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_redirect/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_redirect/composer.json
index 2c425ccd88..509edcc60c 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_redirect/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_redirect/composer.json
@@ -1,4 +1,4 @@
-@@ -20,7 +20,6 @@
+@@ -21,7 +21,6 @@
          "drupal/generated_content": "__VERSION__",
          "drupal/navigation_extra_tools": "__VERSION__",
          "drupal/pathauto": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/composer.json
index 8d714c148b..96d8498c19 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/composer.json
@@ -1,4 +1,4 @@
-@@ -22,7 +22,6 @@
+@@ -23,7 +23,6 @@
          "drupal/pathauto": "__VERSION__",
          "drupal/redirect": "__VERSION__",
          "drupal/redis": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index ea3870a1f9..2984bea6a8 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -16,7 +16,7 @@
        'sdc_devel',
        'testmode',
      ];
-@@ -162,9 +158,6 @@
+@@ -174,9 +170,6 @@
      $config['shield.settings']['shield_enable'] = TRUE;
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
@@ -26,7 +26,7 @@
      $config['system.performance']['cache']['page']['max_age'] = 1800;
      $this->assertConfig($config);
  
-@@ -173,7 +166,6 @@
+@@ -185,7 +178,6 @@
      $settings['config_exclude_modules'] = [
        'devel',
        'generated_content',
@@ -34,7 +34,7 @@
        'sdc_devel',
        'testmode',
      ];
-@@ -220,9 +212,6 @@
+@@ -243,9 +235,6 @@
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['system.logging']['error_level'] = 'all';
      $config['system.performance']['cache']['page']['max_age'] = 900;
@@ -44,7 +44,7 @@
      $config['seckit.settings']['seckit_xss']['csp']['checkbox'] = FALSE;
      $config['seckit.settings']['seckit_xss']['csp']['upgrade-req'] = FALSE;
      $this->assertConfig($config);
-@@ -231,7 +220,6 @@
+@@ -254,7 +243,6 @@
      $settings['config_exclude_modules'] = [
        'devel',
        'generated_content',
@@ -52,7 +52,7 @@
        'sdc_devel',
        'testmode',
      ];
-@@ -278,9 +266,6 @@
+@@ -313,9 +301,6 @@
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['system.logging']['error_level'] = 'all';
      $config['system.performance']['cache']['page']['max_age'] = 900;
@@ -62,7 +62,7 @@
      $config['seckit.settings']['seckit_xss']['csp']['checkbox'] = FALSE;
      $config['seckit.settings']['seckit_xss']['csp']['upgrade-req'] = FALSE;
      $this->assertConfig($config);
-@@ -289,7 +274,6 @@
+@@ -324,7 +309,6 @@
      $settings['config_exclude_modules'] = [
        'devel',
        'generated_content',
@@ -70,7 +70,7 @@
        'sdc_devel',
        'testmode',
      ];
-@@ -379,9 +363,6 @@
+@@ -426,9 +410,6 @@
      $config['system.logging']['error_level'] = 'all';
      $config['system.mail']['interface']['default'] = 'test_mail_collector';
      $config['system.performance']['cache']['page']['max_age'] = 900;
@@ -80,7 +80,7 @@
      $config['seckit.settings']['seckit_xss']['csp']['checkbox'] = FALSE;
      $config['seckit.settings']['seckit_xss']['csp']['upgrade-req'] = FALSE;
      $this->assertConfig($config);
-@@ -390,7 +371,6 @@
+@@ -437,7 +418,6 @@
      $settings['config_exclude_modules'] = [
        'devel',
        'generated_content',
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 2c1705e3eb..371b43742b 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_reroute_email/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -665,156 +665,6 @@
+@@ -780,156 +780,6 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_robotstxt/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_robotstxt/composer.json
index 47c0a5c760..22d552aa68 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_robotstxt/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_robotstxt/composer.json
@@ -1,4 +1,4 @@
-@@ -23,7 +23,6 @@
+@@ -24,7 +24,6 @@
          "drupal/redirect": "__VERSION__",
          "drupal/redis": "__VERSION__",
          "drupal/reroute_email": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_robotstxt/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_robotstxt/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 3d2745c64c..6cf455f914 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_robotstxt/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_robotstxt/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -6,7 +6,7 @@
      $config['shield.settings']['shield_enable'] = TRUE;
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
-@@ -158,7 +157,6 @@
+@@ -170,7 +169,6 @@
      $config['environment_indicator.indicator']['name'] = self::ENVIRONMENT_SUT;
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
@@ -14,7 +14,7 @@
      $config['shield.settings']['shield_enable'] = TRUE;
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
-@@ -214,7 +212,6 @@
+@@ -237,7 +235,6 @@
      $config['environment_indicator.indicator']['name'] = self::ENVIRONMENT_LOCAL;
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
@@ -22,7 +22,7 @@
      $config['shield.settings']['shield_enable'] = FALSE;
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
-@@ -272,7 +269,6 @@
+@@ -307,7 +304,6 @@
      $config['environment_indicator.indicator']['name'] = self::ENVIRONMENT_LOCAL;
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
@@ -30,7 +30,7 @@
      $config['shield.settings']['shield_enable'] = FALSE;
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
-@@ -372,7 +368,6 @@
+@@ -419,7 +415,6 @@
      $config['environment_indicator.indicator']['name'] = self::ENVIRONMENT_CI;
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_sdc_devel/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_sdc_devel/composer.json
index cff02750b8..8020dd7719 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_sdc_devel/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_sdc_devel/composer.json
@@ -1,4 +1,4 @@
-@@ -24,7 +24,6 @@
+@@ -25,7 +25,6 @@
          "drupal/redis": "__VERSION__",
          "drupal/reroute_email": "__VERSION__",
          "drupal/robotstxt": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_sdc_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_sdc_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index c61f428b5a..1b420dba7e 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_sdc_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_sdc_devel/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -6,7 +6,7 @@
        'testmode',
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -174,7 +173,6 @@
+@@ -186,7 +185,6 @@
        'devel',
        'generated_content',
        'reroute_email',
@@ -14,7 +14,7 @@
        'testmode',
      ];
      $settings['config_sync_directory'] = 'custom_config';
-@@ -232,7 +230,6 @@
+@@ -255,7 +253,6 @@
        'devel',
        'generated_content',
        'reroute_email',
@@ -22,7 +22,7 @@
        'testmode',
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -290,7 +287,6 @@
+@@ -325,7 +322,6 @@
        'devel',
        'generated_content',
        'reroute_email',
@@ -30,7 +30,7 @@
        'testmode',
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -391,7 +387,6 @@
+@@ -438,7 +434,6 @@
        'devel',
        'generated_content',
        'reroute_email',
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit/composer.json
index 96b20ce648..fd2e605283 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit/composer.json
@@ -1,4 +1,4 @@
-@@ -27,7 +27,6 @@
+@@ -28,7 +28,6 @@
          "drupal/sdc_devel": "__VERSION__",
          "drupal/search_api": "__VERSION__",
          "drupal/search_api_solr": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index b41a5d5be4..8b8c997a38 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -223,8 +223,6 @@
+@@ -246,8 +246,6 @@
      $config['reroute_email.settings']['enable'] = FALSE;
      $config['reroute_email.settings']['address'] = 'webmaster@star-wars.com';
      $config['reroute_email.settings']['allowed'] = '*@star-wars.com';
@@ -7,7 +7,7 @@
      $this->assertConfig($config);
  
      $settings['auto_create_htaccess'] = FALSE;
-@@ -281,8 +279,6 @@
+@@ -316,8 +314,6 @@
      $config['reroute_email.settings']['enable'] = FALSE;
      $config['reroute_email.settings']['address'] = 'webmaster@star-wars.com';
      $config['reroute_email.settings']['allowed'] = '*@star-wars.com';
@@ -16,7 +16,7 @@
      $this->assertConfig($config);
  
      $settings['auto_create_htaccess'] = FALSE;
-@@ -382,8 +378,6 @@
+@@ -429,8 +425,6 @@
      $config['reroute_email.settings']['enable'] = FALSE;
      $config['reroute_email.settings']['address'] = 'webmaster@star-wars.com';
      $config['reroute_email.settings']['allowed'] = '*@star-wars.com';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/composer.json
index 3536ab6c60..d2cc1f6161 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/composer.json
@@ -1,4 +1,4 @@
-@@ -27,9 +27,6 @@
+@@ -28,9 +28,6 @@
          "drupal/sdc_devel": "__VERSION__",
          "drupal/search_api": "__VERSION__",
          "drupal/search_api_solr": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 5be338c73c..7d6a428549 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -6,7 +6,7 @@
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['reroute_email.settings']['enable'] = TRUE;
-@@ -159,7 +158,6 @@
+@@ -171,7 +170,6 @@
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
@@ -14,7 +14,7 @@
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['reroute_email.settings']['enable'] = TRUE;
-@@ -215,7 +213,6 @@
+@@ -238,7 +236,6 @@
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
@@ -22,7 +22,7 @@
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['system.logging']['error_level'] = 'all';
-@@ -223,8 +220,6 @@
+@@ -246,8 +243,6 @@
      $config['reroute_email.settings']['enable'] = FALSE;
      $config['reroute_email.settings']['address'] = 'webmaster@star-wars.com';
      $config['reroute_email.settings']['allowed'] = '*@star-wars.com';
@@ -31,7 +31,7 @@
      $this->assertConfig($config);
  
      $settings['auto_create_htaccess'] = FALSE;
-@@ -273,7 +268,6 @@
+@@ -308,7 +303,6 @@
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
@@ -39,7 +39,7 @@
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['system.logging']['error_level'] = 'all';
-@@ -281,8 +275,6 @@
+@@ -316,8 +310,6 @@
      $config['reroute_email.settings']['enable'] = FALSE;
      $config['reroute_email.settings']['address'] = 'webmaster@star-wars.com';
      $config['reroute_email.settings']['allowed'] = '*@star-wars.com';
@@ -48,7 +48,7 @@
      $this->assertConfig($config);
  
      $settings['auto_create_htaccess'] = FALSE;
-@@ -373,7 +365,6 @@
+@@ -420,7 +412,6 @@
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
@@ -56,7 +56,7 @@
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['system.logging']['error_level'] = 'all';
-@@ -382,8 +373,6 @@
+@@ -429,8 +420,6 @@
      $config['reroute_email.settings']['enable'] = FALSE;
      $config['reroute_email.settings']['address'] = 'webmaster@star-wars.com';
      $config['reroute_email.settings']['allowed'] = '*@star-wars.com';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/tests/phpunit/Drupal/SwitchableSettingsTest.php
index a075466214..c05bf56247 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_seckit_shield_stage_file_proxy/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -296,375 +296,6 @@
+@@ -411,375 +411,6 @@
    }
  
    /**
@@ -374,7 +374,7 @@
     * Test Reroute Email config.
     */
    #[DataProvider('dataProviderRerouteEmail')]
-@@ -811,131 +442,6 @@
+@@ -926,131 +557,6 @@
        [
          'reroute_email.settings' => ['enable' => FALSE],
        ],
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/composer.json
index b4e960b217..c614485bf4 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/composer.json
@@ -1,4 +1,4 @@
-@@ -28,7 +28,6 @@
+@@ -29,7 +29,6 @@
          "drupal/search_api": "__VERSION__",
          "drupal/search_api_solr": "__VERSION__",
          "drupal/seckit": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index d49055ca19..ee2b089c11 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -6,7 +6,7 @@
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['reroute_email.settings']['enable'] = TRUE;
-@@ -159,7 +158,6 @@
+@@ -171,7 +170,6 @@
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
@@ -14,7 +14,7 @@
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['reroute_email.settings']['enable'] = TRUE;
-@@ -215,7 +213,6 @@
+@@ -238,7 +236,6 @@
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
@@ -22,7 +22,7 @@
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['system.logging']['error_level'] = 'all';
-@@ -273,7 +270,6 @@
+@@ -308,7 +305,6 @@
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
@@ -30,7 +30,7 @@
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['system.logging']['error_level'] = 'all';
-@@ -373,7 +369,6 @@
+@@ -420,7 +416,6 @@
      $config['environment_indicator.settings']['favicon'] = TRUE;
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/tests/phpunit/Drupal/SwitchableSettingsTest.php
index bf029efa47..371119235b 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_shield/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -296,375 +296,6 @@
+@@ -411,375 +411,6 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_stage_file_proxy/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_stage_file_proxy/composer.json
index 76e9c8e34c..cdfd5f0e42 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_stage_file_proxy/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_stage_file_proxy/composer.json
@@ -1,4 +1,4 @@
-@@ -29,7 +29,6 @@
+@@ -30,7 +30,6 @@
          "drupal/search_api_solr": "__VERSION__",
          "drupal/seckit": "__VERSION__",
          "drupal/shield": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_stage_file_proxy/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_stage_file_proxy/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 42e76540b5..58ba7fb82f 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_stage_file_proxy/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_stage_file_proxy/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -815,131 +815,6 @@
+@@ -930,131 +930,6 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_testmode/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_testmode/composer.json
index da730bd25e..eb064138ff 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_testmode/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_testmode/composer.json
@@ -1,4 +1,4 @@
-@@ -30,7 +30,6 @@
+@@ -31,7 +31,6 @@
          "drupal/seckit": "__VERSION__",
          "drupal/shield": "__VERSION__",
          "drupal/stage_file_proxy": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_testmode/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_testmode/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index b4de93c747..3d89c52f6b 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_testmode/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_testmode/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -6,7 +6,7 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -175,7 +174,6 @@
+@@ -187,7 +186,6 @@
        'generated_content',
        'reroute_email',
        'sdc_devel',
@@ -14,7 +14,7 @@
      ];
      $settings['config_sync_directory'] = 'custom_config';
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -233,7 +231,6 @@
+@@ -256,7 +254,6 @@
        'generated_content',
        'reroute_email',
        'sdc_devel',
@@ -22,7 +22,7 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -291,7 +288,6 @@
+@@ -326,7 +323,6 @@
        'generated_content',
        'reroute_email',
        'sdc_devel',
@@ -30,7 +30,7 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -392,7 +388,6 @@
+@@ -439,7 +435,6 @@
        'generated_content',
        'reroute_email',
        'sdc_devel',
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_xmlsitemap/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_no_xmlsitemap/composer.json
index 81380780a5..45bc2df4c9 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_xmlsitemap/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_xmlsitemap/composer.json
@@ -1,4 +1,4 @@
-@@ -31,7 +31,6 @@
+@@ -32,7 +32,6 @@
          "drupal/shield": "__VERSION__",
          "drupal/stage_file_proxy": "__VERSION__",
          "drupal/testmode": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_no_xmlsitemap/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_no_xmlsitemap/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index d687d58cac..76d02a4739 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_no_xmlsitemap/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_no_xmlsitemap/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -6,7 +6,7 @@
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['reroute_email.settings']['enable'] = TRUE;
      $config['reroute_email.settings']['address'] = 'webmaster@star-wars.com';
-@@ -160,7 +159,6 @@
+@@ -172,7 +171,6 @@
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
      $config['shield.settings']['shield_enable'] = TRUE;
@@ -14,7 +14,7 @@
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['reroute_email.settings']['enable'] = TRUE;
      $config['reroute_email.settings']['address'] = 'webmaster@star-wars.com';
-@@ -216,7 +214,6 @@
+@@ -239,7 +237,6 @@
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
      $config['shield.settings']['shield_enable'] = FALSE;
@@ -22,7 +22,7 @@
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['system.logging']['error_level'] = 'all';
      $config['system.performance']['cache']['page']['max_age'] = 900;
-@@ -274,7 +271,6 @@
+@@ -309,7 +306,6 @@
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
      $config['shield.settings']['shield_enable'] = FALSE;
@@ -30,7 +30,7 @@
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['system.logging']['error_level'] = 'all';
      $config['system.performance']['cache']['page']['max_age'] = 900;
-@@ -374,7 +370,6 @@
+@@ -421,7 +417,6 @@
      $config['environment_indicator.settings']['toolbar_integration'] = [TRUE];
      $config['robotstxt.settings']['content'] = "User-agent: *\nDisallow: /";
      $config['shield.settings']['shield_enable'] = FALSE;
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_none/composer.json b/.vortex/installer/tests/Fixtures/handler_process/modules_none/composer.json
index 31cc5c9bd1..69ee91580d 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_none/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_none/composer.json
@@ -1,4 +1,4 @@
-@@ -9,29 +9,11 @@
+@@ -9,30 +9,11 @@
          "cweagans/composer-patches": "__VERSION__",
          "drevops/vortex-tooling": "__VERSION__",
          "drupal/clamav": "__VERSION__",
@@ -10,6 +10,7 @@
 -        "drupal/devel": "__VERSION__",
 -        "drupal/drupal_helpers": "__VERSION__",
 -        "drupal/environment_indicator": "__VERSION__",
+-        "drupal/fast_404": "__VERSION__",
 -        "drupal/generated_content": "__VERSION__",
 -        "drupal/navigation_extra_tools": "__VERSION__",
 -        "drupal/pathauto": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_none/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_none/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 3f380ed505..a300a6168b 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_none/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_none/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -70,28 +70,12 @@
+@@ -70,43 +70,16 @@
  
      $this->requireSettingsFile();
  
@@ -27,7 +27,22 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -153,18 +137,7 @@
+     $settings['environment'] = self::ENVIRONMENT_SUT;
+-    $settings['fast404_allow_anon_imagecache'] = TRUE;
+-    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+-    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+-    $settings['fast404_whitelist'] = [
+-      'index.php',
+-      'rss.xml',
+-      'install.php',
+-      'cron.php',
+-      'update.php',
+-      'xmlrpc.php',
+-    ];
+     $settings['file_public_path'] = 'sites/default/files';
+     $settings['file_private_path'] = 'sites/default/files/private';
+     $settings['file_temp_path'] = '/tmp';
+@@ -165,18 +138,7 @@
      $this->assertEquals($databases, $this->databases);
  
      // Verify key config overrides.
@@ -46,7 +61,7 @@
      $config['system.performance']['cache']['page']['max_age'] = 1800;
      $this->assertConfig($config);
  
-@@ -171,11 +144,6 @@
+@@ -183,27 +145,11 @@
      // Verify settings overrides.
      $settings['auto_create_htaccess'] = FALSE;
      $settings['config_exclude_modules'] = [
@@ -58,7 +73,23 @@
      ];
      $settings['config_sync_directory'] = 'custom_config';
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
-@@ -208,32 +176,13 @@
+     $settings['entity_update_batch_size'] = 50;
+     $settings['environment'] = self::ENVIRONMENT_SUT;
+-    $settings['fast404_allow_anon_imagecache'] = TRUE;
+-    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+-    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+-    $settings['fast404_whitelist'] = [
+-      'index.php',
+-      'rss.xml',
+-      'install.php',
+-      'cron.php',
+-      'update.php',
+-      'xmlrpc.php',
+-    ];
+     $settings['file_public_path'] = 'custom_public';
+     $settings['file_private_path'] = 'custom_private';
+     $settings['file_temp_path'] = 'custom_temp';
+@@ -231,47 +177,17 @@
      $this->requireSettingsFile();
  
      $config['automated_cron.settings']['interval'] = 0;
@@ -91,7 +122,22 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -266,32 +215,13 @@
+     $settings['environment'] = self::ENVIRONMENT_LOCAL;
+-    $settings['fast404_allow_anon_imagecache'] = TRUE;
+-    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+-    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+-    $settings['fast404_whitelist'] = [
+-      'index.php',
+-      'rss.xml',
+-      'install.php',
+-      'cron.php',
+-      'update.php',
+-      'xmlrpc.php',
+-    ];
+     $settings['file_public_path'] = 'sites/default/files';
+     $settings['file_private_path'] = 'sites/default/files/private';
+     $settings['file_temp_path'] = '/tmp';
+@@ -301,47 +217,17 @@
      $this->requireSettingsFile();
  
      $config['automated_cron.settings']['interval'] = 0;
@@ -124,7 +170,22 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
-@@ -366,33 +296,14 @@
+     $settings['environment'] = self::ENVIRONMENT_LOCAL;
+-    $settings['fast404_allow_anon_imagecache'] = TRUE;
+-    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+-    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+-    $settings['fast404_whitelist'] = [
+-      'index.php',
+-      'rss.xml',
+-      'install.php',
+-      'cron.php',
+-      'update.php',
+-      'xmlrpc.php',
+-    ];
+     $settings['file_public_path'] = 'sites/default/files';
+     $settings['file_private_path'] = 'sites/default/files/private';
+     $settings['file_temp_path'] = '/tmp';
+@@ -413,48 +299,18 @@
      $this->requireSettingsFile();
  
      $config['automated_cron.settings']['interval'] = 0;
@@ -158,3 +219,18 @@
      ];
      $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
      $settings['entity_update_batch_size'] = 50;
+     $settings['environment'] = self::ENVIRONMENT_CI;
+-    $settings['fast404_allow_anon_imagecache'] = TRUE;
+-    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+-    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+-    $settings['fast404_whitelist'] = [
+-      'index.php',
+-      'rss.xml',
+-      'install.php',
+-      'cron.php',
+-      'update.php',
+-      'xmlrpc.php',
+-    ];
+     $settings['file_public_path'] = 'sites/default/files';
+     $settings['file_private_path'] = 'sites/default/files/private';
+     $settings['file_temp_path'] = '/tmp';
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_none/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/modules_none/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 2b1419fd75..5b1819d717 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/modules_none/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/modules_none/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,4 +1,36 @@
-@@ -76,154 +76,6 @@
+@@ -4,8 +4,6 @@
+ 
+ namespace Drupal;
+ 
+-use PHPUnit\Framework\Attributes\PreserveGlobalState;
+-use PHPUnit\Framework\Attributes\RunInSeparateProcess;
+ use PHPUnit\Framework\Attributes\DataProvider;
+ use PHPUnit\Framework\Attributes\Group;
+ 
+@@ -22,22 +20,6 @@
+ class SwitchableSettingsTest extends SettingsTestCase {
+ 
+   /**
+-   * Path to the contrib modules directory fixture.
+-   */
+-  protected ?string $contribFixture = NULL;
+-
+-  /**
+-   * {@inheritdoc}
+-   */
+-  protected function tearDown(): void {
+-    if (!is_null($this->contribFixture)) {
+-      $this->removeContribFixture($this->contribFixture);
+-    }
+-
+-    parent::tearDown();
+-  }
+-
+-  /**
+    * Test ClamAV configs in Daemon mode with defaults.
+    */
+   public function testClamavDaemonCustom(): void {
+@@ -94,251 +76,6 @@
    }
  
    /**
@@ -149,11 +181,108 @@
 -    ];
 -  }
 -
+-  /**
+-   * Test Fast 404 settings.
+-   *
+-   * Runs isolated so that the module stub owns the 'fast404_preboot()'
+-   * declaration and its invocation marker is conclusive.
+-   */
+-  #[DataProvider('dataProviderFast404')]
+-  #[RunInSeparateProcess]
+-  #[PreserveGlobalState(FALSE)]
+-  public function testFast404(bool $module_installed, array $expected_present, array $expected_absent = []): void {
+-    $contrib_path = $this->createContribFixture($module_installed);
+-
+-    $this->requireModuleSettingsFile('fast_404', $contrib_path);
+-
+-    $this->assertSettingsContains($expected_present);
+-    $this->assertSettingsNotContains($expected_absent);
+-    $this->assertSame($module_installed, file_exists($contrib_path . '/fast_404/preboot'), 'Preboot invocation');
+-  }
+-
+-  /**
+-   * Data provider for testFast404().
+-   */
+-  public static function dataProviderFast404(): \Iterator {
+-    yield 'module installed' => [
+-      TRUE,
+-      [
+-        'fast404_exts' => '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i',
+-        'fast404_allow_anon_imagecache' => TRUE,
+-        'fast404_whitelist' => ['index.php', 'rss.xml', 'install.php', 'cron.php', 'update.php', 'xmlrpc.php'],
+-        'fast404_html' => '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>',
+-      ],
+-    ];
+-    yield 'module not installed' => [
+-      FALSE,
+-      [],
+-      [
+-        'fast404_exts' => NULL,
+-        'fast404_allow_anon_imagecache' => NULL,
+-        'fast404_whitelist' => NULL,
+-        'fast404_html' => NULL,
+-      ],
+-    ];
+-  }
+-
+-  /**
+-   * Create a contrib modules directory fixture.
+-   *
+-   * The Fast 404 module is not required by the project, so its settings file
+-   * guard can only be satisfied by a stub.
+-   *
+-   * @param bool $with_fast404
+-   *   Create a stub of the Fast 404 module within the fixture. The stub marks
+-   *   the directory when its preboot function is called.
+-   *
+-   * @return string
+-   *   Path to the contrib modules directory fixture.
+-   */
+-  protected function createContribFixture(bool $with_fast404): string {
+-    $this->contribFixture = getcwd() . '/.artifacts/tmp/' . uniqid('contrib-');
+-
+-    mkdir($this->contribFixture, 0777, TRUE);
+-
+-    if ($with_fast404) {
+-      $stub = <<<'PHP'
+-        <?php
+-
+-        function fast404_preboot(array $settings = []): void {
+-          touch(__DIR__ . '/preboot');
+-        }
+-
+-        PHP;
+-
+-      mkdir($this->contribFixture . '/fast_404');
+-      file_put_contents($this->contribFixture . '/fast_404/fast404.inc', $stub);
+-    }
+-
+-    return $this->contribFixture;
+-  }
+-
+-  /**
+-   * Remove the contrib modules directory fixture.
+-   *
+-   * @param string $path
+-   *   Path to the contrib modules directory fixture.
+-   */
+-  protected function removeContribFixture(string $path): void {
+-    foreach (glob($path . '/*/*') ?: [] as $file) {
+-      unlink($file);
+-    }
+-
+-    foreach (glob($path . '/*', GLOB_ONLYDIR) ?: [] as $dir) {
+-      rmdir($dir);
+-    }
+-
+-    rmdir($path);
+-  }
+-
 -  /**
     * Test Redis settings.
     */
    public function testRedis(): void {
-@@ -293,650 +145,6 @@
+@@ -408,650 +145,6 @@
      unset($this->settings['bootstrap_container_definition']);
  
      $this->assertSettingsContains($settings);
diff --git a/.vortex/installer/tests/Fixtures/handler_process/modules_none/web/sites/default/includes/modules/-settings.fast_404.php b/.vortex/installer/tests/Fixtures/handler_process/modules_none/web/sites/default/includes/modules/-settings.fast_404.php
new file mode 100644
index 0000000000..e69de29bb2
diff --git a/.vortex/installer/tests/Fixtures/handler_process/names/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/names/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 8b03a87db3..abc2b5a74e 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/names/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/names/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -9,7 +9,7 @@
      $config['system.performance']['cache']['page']['max_age'] = 900;
      $this->assertConfig($config);
  
-@@ -163,8 +163,8 @@
+@@ -175,8 +175,8 @@
      $config['xmlsitemap.settings']['disable_cron_regeneration'] = TRUE;
      $config['xmlsitemap_engines.settings']['submit'] = FALSE;
      $config['reroute_email.settings']['enable'] = TRUE;
@@ -20,7 +20,7 @@
      $config['system.performance']['cache']['page']['max_age'] = 1800;
      $this->assertConfig($config);
  
-@@ -221,8 +221,8 @@
+@@ -244,8 +244,8 @@
      $config['system.logging']['error_level'] = 'all';
      $config['system.performance']['cache']['page']['max_age'] = 900;
      $config['reroute_email.settings']['enable'] = FALSE;
@@ -31,7 +31,7 @@
      $config['seckit.settings']['seckit_xss']['csp']['checkbox'] = FALSE;
      $config['seckit.settings']['seckit_xss']['csp']['upgrade-req'] = FALSE;
      $this->assertConfig($config);
-@@ -279,8 +279,8 @@
+@@ -314,8 +314,8 @@
      $config['system.logging']['error_level'] = 'all';
      $config['system.performance']['cache']['page']['max_age'] = 900;
      $config['reroute_email.settings']['enable'] = FALSE;
@@ -42,7 +42,7 @@
      $config['seckit.settings']['seckit_xss']['csp']['checkbox'] = FALSE;
      $config['seckit.settings']['seckit_xss']['csp']['upgrade-req'] = FALSE;
      $this->assertConfig($config);
-@@ -380,8 +380,8 @@
+@@ -427,8 +427,8 @@
      $config['system.mail']['interface']['default'] = 'test_mail_collector';
      $config['system.performance']['cache']['page']['max_age'] = 900;
      $config['reroute_email.settings']['enable'] = FALSE;
diff --git a/.vortex/installer/tests/Fixtures/handler_process/names/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/names/tests/phpunit/Drupal/SwitchableSettingsTest.php
index b99ef526c3..a9582593fd 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/names/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/names/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -686,7 +686,7 @@
+@@ -801,7 +801,7 @@
        self::ENVIRONMENT_LOCAL,
        [],
        [
@@ -7,7 +7,7 @@
        ],
      ];
  
-@@ -695,7 +695,7 @@
+@@ -810,7 +810,7 @@
        self::ENVIRONMENT_CI,
        [],
        [
@@ -16,7 +16,7 @@
        ],
      ];
  
-@@ -704,7 +704,7 @@
+@@ -819,7 +819,7 @@
        self::ENVIRONMENT_DEV,
        [],
        [
@@ -25,7 +25,7 @@
        ],
      ];
  
-@@ -713,7 +713,7 @@
+@@ -828,7 +828,7 @@
        self::ENVIRONMENT_SUT,
        [],
        [
@@ -34,7 +34,7 @@
        ],
      ];
  
-@@ -722,7 +722,7 @@
+@@ -837,7 +837,7 @@
        self::ENVIRONMENT_STAGE,
        [],
        [
@@ -43,7 +43,7 @@
        ],
      ];
  
-@@ -731,7 +731,7 @@
+@@ -846,7 +846,7 @@
        self::ENVIRONMENT_PROD,
        [],
        [
diff --git a/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_file/composer.json b/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_file/composer.json
index c5755fadb1..a5a7d2f740 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_file/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_file/composer.json
@@ -7,7 +7,7 @@
      "license": "proprietary",
      "type": "project",
      "require": {
-@@ -21,7 +21,6 @@
+@@ -22,7 +22,6 @@
          "drupal/navigation_extra_tools": "__VERSION__",
          "drupal/pathauto": "__VERSION__",
          "drupal/redirect": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_file/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_file/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 7a0f40014a..5cc551ee53 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_file/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_file/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -224,78 +224,6 @@
+@@ -339,78 +339,6 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_string/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_string/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 5441d77b3b..a2c5670bb2 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_string/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/non_interactive_config_string/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,5 +1,5 @@
-@@ -20,62 +20,6 @@
- class SwitchableSettingsTest extends SettingsTestCase {
+@@ -38,62 +38,6 @@
+   }
  
    /**
 -   * Test ClamAV configs in Daemon mode with defaults.
diff --git a/.vortex/installer/tests/Fixtures/handler_process/provision_database_lagoon/composer.json b/.vortex/installer/tests/Fixtures/handler_process/provision_database_lagoon/composer.json
index 7813ec6268..0ef00bdaef 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/provision_database_lagoon/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/provision_database_lagoon/composer.json
@@ -1,6 +1,6 @@
-@@ -18,6 +18,7 @@
-         "drupal/drupal_helpers": "__VERSION__",
+@@ -19,6 +19,7 @@
          "drupal/environment_indicator": "__VERSION__",
+         "drupal/fast_404": "__VERSION__",
          "drupal/generated_content": "__VERSION__",
 +        "drupal/lagoon_logs": "__VERSION__",
          "drupal/navigation_extra_tools": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/provision_database_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/provision_database_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index ab2ed9bfa4..7f3b316ae4 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/provision_database_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/provision_database_lagoon/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -185,9 +185,9 @@
    }
  
    /**
-@@ -412,6 +592,287 @@
-       '^localhost$',
+@@ -471,6 +651,335 @@
      ];
+ 
      $this->assertSettings($settings);
 +  }
 +
@@ -235,6 +235,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -253,6 +264,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -300,6 +312,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_DEV;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -318,6 +341,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -365,6 +389,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_STAGE;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -383,6 +418,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
@@ -428,6 +464,17 @@
 +    $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
 +    $settings['entity_update_batch_size'] = 50;
 +    $settings['environment'] = self::ENVIRONMENT_PROD;
++    $settings['fast404_allow_anon_imagecache'] = TRUE;
++    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
++    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
++    $settings['fast404_whitelist'] = [
++      'index.php',
++      'rss.xml',
++      'install.php',
++      'cron.php',
++      'update.php',
++      'xmlrpc.php',
++    ];
 +    $settings['file_public_path'] = 'sites/default/files';
 +    $settings['file_private_path'] = 'sites/default/files/private';
 +    $settings['file_temp_path'] = '/tmp';
@@ -446,6 +493,7 @@
 +      '^example1\.com$',
 +      '^example2$',
 +    ];
++
 +    $this->assertSettings($settings);
 +  }
 +
diff --git a/.vortex/installer/tests/Fixtures/handler_process/services_no_clamav/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/services_no_clamav/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 5441d77b3b..a2c5670bb2 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/services_no_clamav/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/services_no_clamav/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,5 +1,5 @@
-@@ -20,62 +20,6 @@
- class SwitchableSettingsTest extends SettingsTestCase {
+@@ -38,62 +38,6 @@
+   }
  
    /**
 -   * Test ClamAV configs in Daemon mode with defaults.
diff --git a/.vortex/installer/tests/Fixtures/handler_process/services_no_redis/composer.json b/.vortex/installer/tests/Fixtures/handler_process/services_no_redis/composer.json
index 63bd25f160..03f9dd2a33 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/services_no_redis/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/services_no_redis/composer.json
@@ -1,4 +1,4 @@
-@@ -21,7 +21,6 @@
+@@ -22,7 +22,6 @@
          "drupal/navigation_extra_tools": "__VERSION__",
          "drupal/pathauto": "__VERSION__",
          "drupal/redirect": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/services_no_redis/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/services_no_redis/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 7a0f40014a..5cc551ee53 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/services_no_redis/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/services_no_redis/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -224,78 +224,6 @@
+@@ -339,78 +339,6 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/services_no_solr/composer.json b/.vortex/installer/tests/Fixtures/handler_process/services_no_solr/composer.json
index 856b514cc9..e602c50434 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/services_no_solr/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/services_no_solr/composer.json
@@ -1,4 +1,4 @@
-@@ -26,7 +26,6 @@
+@@ -27,7 +27,6 @@
          "drupal/robotstxt": "__VERSION__",
          "drupal/sdc_devel": "__VERSION__",
          "drupal/search_api": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/services_none/composer.json b/.vortex/installer/tests/Fixtures/handler_process/services_none/composer.json
index 12736185df..94759f7d30 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/services_none/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/services_none/composer.json
@@ -6,7 +6,7 @@
          "drupal/coffee": "__VERSION__",
          "drupal/config_split": "__VERSION__",
          "drupal/config_update": "__VERSION__",
-@@ -21,12 +20,10 @@
+@@ -22,12 +21,10 @@
          "drupal/navigation_extra_tools": "__VERSION__",
          "drupal/pathauto": "__VERSION__",
          "drupal/redirect": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/services_none/tests/phpunit/Drupal/SwitchableSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/services_none/tests/phpunit/Drupal/SwitchableSettingsTest.php
index 115cd6d5c4..700e7a004d 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/services_none/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/services_none/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -1,5 +1,5 @@
-@@ -20,62 +20,6 @@
- class SwitchableSettingsTest extends SettingsTestCase {
+@@ -38,62 +38,6 @@
+   }
  
    /**
 -   * Test ClamAV configs in Daemon mode with defaults.
@@ -61,10 +61,10 @@ class SwitchableSettingsTest extends SettingsTestCase {
     * Test Config Split config.
     */
    #[DataProvider('dataProviderConfigSplit')]
-@@ -221,78 +165,6 @@
-         'environment_indicator.settings' => ['toolbar_integration' => [TRUE], 'favicon' => TRUE],
-       ],
-     ];
+@@ -336,78 +280,6 @@
+     }
+ 
+     rmdir($path);
 -  }
 -
 -  /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/starter_drupal_cms_profile/composer.json b/.vortex/installer/tests/Fixtures/handler_process/starter_drupal_cms_profile/composer.json
index 2a988a55c6..8448d72c07 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/starter_drupal_cms_profile/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/starter_drupal_cms_profile/composer.json
@@ -6,7 +6,7 @@
          "drupal/coffee": "__VERSION__",
          "drupal/config_split": "__VERSION__",
          "drupal/config_update": "__VERSION__",
-@@ -32,7 +33,9 @@
+@@ -33,7 +34,9 @@
          "drupal/stage_file_proxy": "__VERSION__",
          "drupal/testmode": "__VERSION__",
          "drupal/xmlsitemap": "__VERSION__",
@@ -17,7 +17,7 @@
      },
      "require-dev": {
          "behat/behat": "__VERSION__",
-@@ -65,7 +68,7 @@
+@@ -66,7 +69,7 @@
              "url": "https://packages.drupal.org/8"
          }
      ],
@@ -26,7 +26,7 @@
      "prefer-stable": true,
      "autoload-dev": {
          "classmap": [
-@@ -83,7 +86,11 @@
+@@ -84,7 +87,11 @@
              "phpstan/extension-installer": true,
              "pyrech/composer-changelogs": true,
              "symfony/runtime": true,
@@ -39,7 +39,7 @@
          },
          "bump-after-update": true,
          "discard-changes": true,
-@@ -158,6 +165,17 @@
+@@ -159,6 +166,17 @@
          "patchLevel": {
              "drupal/core": "-p2"
          },
diff --git a/.vortex/installer/tests/Fixtures/handler_process/timezone_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/timezone_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/timezone_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/timezone_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint/composer.json
index 12091e89d6..06491f51ea 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint/composer.json
@@ -1,4 +1,4 @@
-@@ -40,17 +40,10 @@
+@@ -41,17 +41,10 @@
          "drevops/behat-format-progress-fail": "__VERSION__",
          "drevops/behat-screenshot": "__VERSION__",
          "drevops/behat-steps": "__VERSION__",
@@ -16,7 +16,7 @@
          "phpunit/phpunit": "__VERSION__",
          "pyrech/composer-changelogs": "__VERSION__",
          "softcreatr/jsonpath": "^0.10 || ^1.0",
-@@ -76,11 +69,9 @@
+@@ -77,11 +70,9 @@
          "allow-plugins": {
              "composer/installers": true,
              "cweagans/composer-patches": true,
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/web/sites/default/includes/modules/settings.fast404.php b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint/web/sites/default/includes/modules/settings.fast_404.php
similarity index 70%
rename from .vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/web/sites/default/includes/modules/settings.fast404.php
rename to .vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint/web/sites/default/includes/modules/settings.fast_404.php
index 74b826db06..531f81035a 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/web/sites/default/includes/modules/settings.fast404.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint/web/sites/default/includes/modules/settings.fast_404.php
@@ -1,8 +1,7 @@
-@@ -22,7 +22,6 @@
-   $settings['fast404_string_whitelisting'] = ['/advagg_'];
+@@ -20,6 +20,5 @@
+   ];
    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
-   include_once $contrib_path . '/fast404/fast404.inc';
+   include_once $contrib_path . '/fast_404/fast404.inc';
 -  // @phpstan-ignore-next-line
    fast404_preboot($settings);
-   // @codeCoverageIgnoreEnd
  }
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/composer.json
index 12091e89d6..06491f51ea 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/composer.json
@@ -1,4 +1,4 @@
-@@ -40,17 +40,10 @@
+@@ -41,17 +41,10 @@
          "drevops/behat-format-progress-fail": "__VERSION__",
          "drevops/behat-screenshot": "__VERSION__",
          "drevops/behat-steps": "__VERSION__",
@@ -16,7 +16,7 @@
          "phpunit/phpunit": "__VERSION__",
          "pyrech/composer-changelogs": "__VERSION__",
          "softcreatr/jsonpath": "^0.10 || ^1.0",
-@@ -76,11 +69,9 @@
+@@ -77,11 +70,9 @@
          "allow-plugins": {
              "composer/installers": true,
              "cweagans/composer-patches": true,
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 1b2577e8cb..5452ce5f36 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -9,7 +9,7 @@
   */
  #[Group('drupal_settings')]
  class EnvironmentSettingsTest extends SettingsTestCase {
-@@ -356,9 +352,9 @@
+@@ -403,9 +399,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan/web/sites/default/includes/modules/settings.fast404.php b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/web/sites/default/includes/modules/settings.fast_404.php
similarity index 70%
rename from .vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan/web/sites/default/includes/modules/settings.fast404.php
rename to .vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/web/sites/default/includes/modules/settings.fast_404.php
index 74b826db06..531f81035a 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan/web/sites/default/includes/modules/settings.fast404.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint_circleci/web/sites/default/includes/modules/settings.fast_404.php
@@ -1,8 +1,7 @@
-@@ -22,7 +22,6 @@
-   $settings['fast404_string_whitelisting'] = ['/advagg_'];
+@@ -20,6 +20,5 @@
+   ];
    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
-   include_once $contrib_path . '/fast404/fast404.inc';
+   include_once $contrib_path . '/fast_404/fast404.inc';
 -  // @phpstan-ignore-next-line
    fast404_preboot($settings);
-   // @codeCoverageIgnoreEnd
  }
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_tests/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_tests/composer.json
index 238bd99345..c186489cf3 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_tests/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_tests/composer.json
@@ -1,4 +1,4 @@
-@@ -35,23 +35,15 @@
+@@ -36,23 +36,15 @@
          "drush/drush": "__VERSION__"
      },
      "require-dev": {
@@ -22,7 +22,7 @@
          "pyrech/composer-changelogs": "__VERSION__",
          "softcreatr/jsonpath": "^0.10 || ^1.0",
          "vincentlanglet/twig-cs-fixer": "__VERSION__"
-@@ -67,11 +59,6 @@
+@@ -68,11 +60,6 @@
      ],
      "minimum-stability": "stable",
      "prefer-stable": true,
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_tests_circleci/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_tests_circleci/composer.json
index 238bd99345..c186489cf3 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_tests_circleci/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_tests_circleci/composer.json
@@ -1,4 +1,4 @@
-@@ -35,23 +35,15 @@
+@@ -36,23 +36,15 @@
          "drush/drush": "__VERSION__"
      },
      "require-dev": {
@@ -22,7 +22,7 @@
          "pyrech/composer-changelogs": "__VERSION__",
          "softcreatr/jsonpath": "^0.10 || ^1.0",
          "vincentlanglet/twig-cs-fixer": "__VERSION__"
-@@ -67,11 +59,6 @@
+@@ -68,11 +60,6 @@
      ],
      "minimum-stability": "stable",
      "prefer-stable": true,
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_fe_lint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_fe_lint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_fe_lint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_fe_lint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_fe_lint_no_theme_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_fe_lint_no_theme_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_fe_lint_no_theme_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_fe_lint_no_theme_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat/composer.json
index f275b2cda5..9a5abe66df 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat/composer.json
@@ -1,4 +1,4 @@
-@@ -35,14 +35,8 @@
+@@ -36,14 +36,8 @@
          "drush/drush": "__VERSION__"
      },
      "require-dev": {
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat_circleci/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat_circleci/composer.json
index f275b2cda5..9a5abe66df 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat_circleci/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat_circleci/composer.json
@@ -1,4 +1,4 @@
-@@ -35,14 +35,8 @@
+@@ -36,14 +36,8 @@
          "drush/drush": "__VERSION__"
      },
      "require-dev": {
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_behat_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_dclint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_dclint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_dclint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_dclint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_docker_linters_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_docker_linters_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_docker_linters_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_docker_linters_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_eslint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_eslint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_eslint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_eslint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_hadolint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_hadolint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_hadolint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_hadolint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_jest_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_jest_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_jest_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_jest_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs/composer.json
index dc2f444123..29ff9be5e0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs/composer.json
@@ -1,4 +1,4 @@
-@@ -40,14 +40,11 @@
+@@ -41,14 +41,11 @@
          "drevops/behat-format-progress-fail": "__VERSION__",
          "drevops/behat-screenshot": "__VERSION__",
          "drevops/behat-steps": "__VERSION__",
@@ -13,7 +13,7 @@
          "phpspec/prophecy-phpunit": "__VERSION__",
          "phpstan/extension-installer": "__VERSION__",
          "phpstan/phpstan": "__VERSION__",
-@@ -76,7 +73,6 @@
+@@ -77,7 +74,6 @@
          "allow-plugins": {
              "composer/installers": true,
              "cweagans/composer-patches": true,
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs_circleci/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs_circleci/composer.json
index dc2f444123..29ff9be5e0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs_circleci/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs_circleci/composer.json
@@ -1,4 +1,4 @@
-@@ -40,14 +40,11 @@
+@@ -41,14 +41,11 @@
          "drevops/behat-format-progress-fail": "__VERSION__",
          "drevops/behat-screenshot": "__VERSION__",
          "drevops/behat-steps": "__VERSION__",
@@ -13,7 +13,7 @@
          "phpspec/prophecy-phpunit": "__VERSION__",
          "phpstan/extension-installer": "__VERSION__",
          "phpstan/phpstan": "__VERSION__",
-@@ -76,7 +73,6 @@
+@@ -77,7 +74,6 @@
          "allow-plugins": {
              "composer/installers": true,
              "cweagans/composer-patches": true,
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 1b2577e8cb..5452ce5f36 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpcs_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -9,7 +9,7 @@
   */
  #[Group('drupal_settings')]
  class EnvironmentSettingsTest extends SettingsTestCase {
-@@ -356,9 +352,9 @@
+@@ -403,9 +399,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan/composer.json
index 81333b6fd8..a509248ce2 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan/composer.json
@@ -1,4 +1,4 @@
-@@ -44,13 +44,10 @@
+@@ -45,13 +45,10 @@
          "drupal/coder": "__VERSION__",
          "drupal/drupal-extension": "__VERSION__",
          "ergebnis/composer-normalize": "__VERSION__",
@@ -12,7 +12,7 @@
          "phpunit/phpunit": "__VERSION__",
          "pyrech/composer-changelogs": "__VERSION__",
          "softcreatr/jsonpath": "^0.10 || ^1.0",
-@@ -80,7 +77,6 @@
+@@ -81,7 +78,6 @@
              "drupal/core-composer-scaffold": true,
              "ergebnis/composer-normalize": true,
              "php-http/discovery": true,
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/web/sites/default/includes/modules/settings.fast404.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan/web/sites/default/includes/modules/settings.fast_404.php
similarity index 70%
rename from .vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/web/sites/default/includes/modules/settings.fast404.php
rename to .vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan/web/sites/default/includes/modules/settings.fast_404.php
index 74b826db06..531f81035a 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/web/sites/default/includes/modules/settings.fast404.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan/web/sites/default/includes/modules/settings.fast_404.php
@@ -1,8 +1,7 @@
-@@ -22,7 +22,6 @@
-   $settings['fast404_string_whitelisting'] = ['/advagg_'];
+@@ -20,6 +20,5 @@
+   ];
    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
-   include_once $contrib_path . '/fast404/fast404.inc';
+   include_once $contrib_path . '/fast_404/fast404.inc';
 -  // @phpstan-ignore-next-line
    fast404_preboot($settings);
-   // @codeCoverageIgnoreEnd
  }
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/composer.json
index 81333b6fd8..a509248ce2 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/composer.json
@@ -1,4 +1,4 @@
-@@ -44,13 +44,10 @@
+@@ -45,13 +45,10 @@
          "drupal/coder": "__VERSION__",
          "drupal/drupal-extension": "__VERSION__",
          "ergebnis/composer-normalize": "__VERSION__",
@@ -12,7 +12,7 @@
          "phpunit/phpunit": "__VERSION__",
          "pyrech/composer-changelogs": "__VERSION__",
          "softcreatr/jsonpath": "^0.10 || ^1.0",
-@@ -80,7 +77,6 @@
+@@ -81,7 +78,6 @@
              "drupal/core-composer-scaffold": true,
              "ergebnis/composer-normalize": true,
              "php-http/discovery": true,
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint/web/sites/default/includes/modules/settings.fast404.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/web/sites/default/includes/modules/settings.fast_404.php
similarity index 70%
rename from .vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint/web/sites/default/includes/modules/settings.fast404.php
rename to .vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/web/sites/default/includes/modules/settings.fast_404.php
index 74b826db06..531f81035a 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_groups_no_be_lint/web/sites/default/includes/modules/settings.fast404.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpstan_circleci/web/sites/default/includes/modules/settings.fast_404.php
@@ -1,8 +1,7 @@
-@@ -22,7 +22,6 @@
-   $settings['fast404_string_whitelisting'] = ['/advagg_'];
+@@ -20,6 +20,5 @@
+   ];
    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
-   include_once $contrib_path . '/fast404/fast404.inc';
+   include_once $contrib_path . '/fast_404/fast404.inc';
 -  // @phpstan-ignore-next-line
    fast404_preboot($settings);
-   // @codeCoverageIgnoreEnd
  }
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpunit/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpunit/composer.json
index b6640d2d69..c5376599cb 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpunit/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpunit/composer.json
@@ -1,4 +1,4 @@
-@@ -48,10 +48,8 @@
+@@ -49,10 +49,8 @@
          "mikey179/vfsstream": "__VERSION__",
          "palantirnet/drupal-rector": "__VERSION__",
          "phpcompatibility/php-compatibility": "__VERSION__",
@@ -9,7 +9,7 @@
          "pyrech/composer-changelogs": "__VERSION__",
          "softcreatr/jsonpath": "^0.10 || ^1.0",
          "vincentlanglet/twig-cs-fixer": "__VERSION__"
-@@ -67,11 +65,6 @@
+@@ -68,11 +66,6 @@
      ],
      "minimum-stability": "stable",
      "prefer-stable": true,
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpunit_circleci/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpunit_circleci/composer.json
index b6640d2d69..c5376599cb 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpunit_circleci/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_phpunit_circleci/composer.json
@@ -1,4 +1,4 @@
-@@ -48,10 +48,8 @@
+@@ -49,10 +49,8 @@
          "mikey179/vfsstream": "__VERSION__",
          "palantirnet/drupal-rector": "__VERSION__",
          "phpcompatibility/php-compatibility": "__VERSION__",
@@ -9,7 +9,7 @@
          "pyrech/composer-changelogs": "__VERSION__",
          "softcreatr/jsonpath": "^0.10 || ^1.0",
          "vincentlanglet/twig-cs-fixer": "__VERSION__"
-@@ -67,11 +65,6 @@
+@@ -68,11 +66,6 @@
      ],
      "minimum-stability": "stable",
      "prefer-stable": true,
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector/composer.json
index 8521d5fe57..2c6871fa54 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector/composer.json
@@ -1,4 +1,4 @@
-@@ -46,7 +46,6 @@
+@@ -47,7 +47,6 @@
          "ergebnis/composer-normalize": "__VERSION__",
          "mglaman/phpstan-drupal": "__VERSION__",
          "mikey179/vfsstream": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector_circleci/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector_circleci/composer.json
index 8521d5fe57..2c6871fa54 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector_circleci/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector_circleci/composer.json
@@ -1,4 +1,4 @@
-@@ -46,7 +46,6 @@
+@@ -47,7 +47,6 @@
          "ergebnis/composer-normalize": "__VERSION__",
          "mglaman/phpstan-drupal": "__VERSION__",
          "mikey179/vfsstream": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_rector_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_stylelint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_stylelint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_stylelint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_stylelint_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig/composer.json
index 68844dc9dd..cb093527ef 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig/composer.json
@@ -1,4 +1,4 @@
-@@ -53,8 +53,7 @@
+@@ -54,8 +54,7 @@
          "phpstan/phpstan": "__VERSION__",
          "phpunit/phpunit": "__VERSION__",
          "pyrech/composer-changelogs": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig_circleci/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig_circleci/composer.json
index 68844dc9dd..cb093527ef 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig_circleci/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig_circleci/composer.json
@@ -1,4 +1,4 @@
-@@ -53,8 +53,7 @@
+@@ -54,8 +54,7 @@
          "phpstan/phpstan": "__VERSION__",
          "phpunit/phpunit": "__VERSION__",
          "pyrech/composer-changelogs": "__VERSION__",
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 158e13f0a7..49f994e8f0 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_no_twig_circleci/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -1,4 +1,4 @@
-@@ -356,9 +356,9 @@
+@@ -403,9 +403,9 @@
    }
  
    /**
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_none/composer.json b/.vortex/installer/tests/Fixtures/handler_process/tools_none/composer.json
index c3e6547b4f..c94b8e2099 100644
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_none/composer.json
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_none/composer.json
@@ -1,4 +1,4 @@
-@@ -35,26 +35,10 @@
+@@ -36,26 +36,10 @@
          "drush/drush": "__VERSION__"
      },
      "require-dev": {
@@ -26,7 +26,7 @@
      },
      "conflict": {
          "drupal/drupal": "*"
-@@ -67,20 +51,13 @@
+@@ -68,20 +52,13 @@
      ],
      "minimum-stability": "stable",
      "prefer-stable": true,
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_none/web/sites/default/includes/modules/settings.fast404.php b/.vortex/installer/tests/Fixtures/handler_process/tools_none/web/sites/default/includes/modules/settings.fast404.php
deleted file mode 100644
index 74b826db06..0000000000
--- a/.vortex/installer/tests/Fixtures/handler_process/tools_none/web/sites/default/includes/modules/settings.fast404.php
+++ /dev/null
@@ -1,8 +0,0 @@
-@@ -22,7 +22,6 @@
-   $settings['fast404_string_whitelisting'] = ['/advagg_'];
-   $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
-   include_once $contrib_path . '/fast404/fast404.inc';
--  // @phpstan-ignore-next-line
-   fast404_preboot($settings);
-   // @codeCoverageIgnoreEnd
- }
diff --git a/.vortex/installer/tests/Fixtures/handler_process/tools_none/web/sites/default/includes/modules/settings.fast_404.php b/.vortex/installer/tests/Fixtures/handler_process/tools_none/web/sites/default/includes/modules/settings.fast_404.php
new file mode 100644
index 0000000000..531f81035a
--- /dev/null
+++ b/.vortex/installer/tests/Fixtures/handler_process/tools_none/web/sites/default/includes/modules/settings.fast_404.php
@@ -0,0 +1,7 @@
+@@ -20,6 +20,5 @@
+   ];
+   $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+   include_once $contrib_path . '/fast_404/fast404.inc';
+-  // @phpstan-ignore-next-line
+   fast404_preboot($settings);
+ }
diff --git a/.vortex/installer/tests/Functional/Prompts/Handlers/ModulesHandlerProcessTest.php b/.vortex/installer/tests/Functional/Prompts/Handlers/ModulesHandlerProcessTest.php
index 8411bdd96e..757cdbea1b 100644
--- a/.vortex/installer/tests/Functional/Prompts/Handlers/ModulesHandlerProcessTest.php
+++ b/.vortex/installer/tests/Functional/Prompts/Handlers/ModulesHandlerProcessTest.php
@@ -48,6 +48,12 @@ public static function dataProviderHandlerProcess(): \Iterator {
       }),
       static::cw(fn(FunctionalTestCase $test) => $test->assertSutNotContains('environment_indicator')),
     ];
+    yield 'modules_no_fast_404' => [
+      static::cw(function ($test): void {
+          $test->prompts[Modules::id()] = static::getModulesExcept('fast_404');
+      }),
+      static::cw(fn(FunctionalTestCase $test) => $test->assertSutNotContains('fast_404')),
+    ];
     yield 'modules_no_generated_content' => [
       static::cw(function ($test): void {
           $test->prompts[Modules::id()] = static::getModulesExcept('generated_content');
diff --git a/.vortex/installer/tests/Unit/Prompts/Handlers/ModulesHandlerDiscoveryTest.php b/.vortex/installer/tests/Unit/Prompts/Handlers/ModulesHandlerDiscoveryTest.php
index d84035eaa0..439c499959 100644
--- a/.vortex/installer/tests/Unit/Prompts/Handlers/ModulesHandlerDiscoveryTest.php
+++ b/.vortex/installer/tests/Unit/Prompts/Handlers/ModulesHandlerDiscoveryTest.php
@@ -44,6 +44,7 @@ function (AbstractHandlerDiscoveryTestCase $test, Config $config): void {
           'drupal/devel' => '^5.5',
           'drupal/drupal_helpers' => '^2.0.1',
           'drupal/environment_indicator' => '^4.0.25',
+          'drupal/fast_404' => '^3.7',
           'drupal/generated_content' => '^2.0.1',
           'drupal/navigation_extra_tools' => '^1.3.2',
           'drupal/pathauto' => '^1.14',
diff --git a/.vortex/tests/phpunit/Functional/AhoyWorkflowTest.php b/.vortex/tests/phpunit/Functional/AhoyWorkflowTest.php
index 827f41749d..f633ca3d3d 100644
--- a/.vortex/tests/phpunit/Functional/AhoyWorkflowTest.php
+++ b/.vortex/tests/phpunit/Functional/AhoyWorkflowTest.php
@@ -70,6 +70,8 @@ public function testAhoyWorkflowStateless(): void {
 
     $this->subtestAhoyLintTests();
 
+    $this->subtestAhoyFast404();
+
     $this->subtestAhoyReset();
 
     $this->subtestAhoyResetHard();
diff --git a/.vortex/tests/phpunit/Traits/Subtests/SubtestAhoyTrait.php b/.vortex/tests/phpunit/Traits/Subtests/SubtestAhoyTrait.php
index b4d7e4c7f5..40718a0361 100644
--- a/.vortex/tests/phpunit/Traits/Subtests/SubtestAhoyTrait.php
+++ b/.vortex/tests/phpunit/Traits/Subtests/SubtestAhoyTrait.php
@@ -1021,6 +1021,22 @@ protected function subtestAhoyRedis(): void {
     $this->logStepFinish();
   }
 
+  protected function subtestAhoyFast404(): void {
+    $this->logStepStart();
+
+    $this->logSubstep('Assert that the preboot error page is served for a missing asset');
+    // Drupal core serves a near-identical 404 page for the same extensions,
+    // so the DOCTYPE from `settings.fast_404.php` is what tells the two apart.
+    $this->assertWebpageContains('/missing.png', '-//W3C//DTD XHTML+RDFa 1.0//EN', 'Error page from `settings.fast_404.php` should be served');
+    $this->assertWebpageContains('/missing.png', 'The requested URL "/missing.png" was not found on this server.', 'Error page should report the request path resolved before Drupal bootstraps');
+
+    $this->logSubstep('Assert that a route served by Drupal is not intercepted');
+    $this->assertWebpageNotContains('/robots.txt', '-//W3C//DTD XHTML+RDFa 1.0//EN', '`robots.txt` is served by a module, so the preboot handler must let it through');
+    $this->assertWebpageContains('/robots.txt', 'User-agent: *', '`robots.txt` should be served by Drupal');
+
+    $this->logStepFinish();
+  }
+
   protected function substepWarmCaches(): void {
     $this->logNote('Warming up caches');
     $this->cmd('ahoy drush cr');
diff --git a/composer.json b/composer.json
index ef5b5ec2e3..b36584c057 100644
--- a/composer.json
+++ b/composer.json
@@ -17,6 +17,7 @@
         "drupal/devel": "^5.5",
         "drupal/drupal_helpers": "^2.1.1",
         "drupal/environment_indicator": "^4.0.25",
+        "drupal/fast_404": "^3.7",
         "drupal/generated_content": "^2.1.1",
         "drupal/migrate_plus": "^6.0.10",
         "drupal/migrate_tools": "^6.1.4",
diff --git a/tests/phpunit/Drupal/EnvironmentSettingsTest.php b/tests/phpunit/Drupal/EnvironmentSettingsTest.php
index 304d9f0ffa..c53d3b713f 100644
--- a/tests/phpunit/Drupal/EnvironmentSettingsTest.php
+++ b/tests/phpunit/Drupal/EnvironmentSettingsTest.php
@@ -334,6 +334,19 @@ public function testEnvironmentNoOverrides(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_SUT;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -347,6 +360,7 @@ public function testEnvironmentNoOverrides(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -438,6 +452,19 @@ public function testEnvironmentOverrides(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_SUT;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'custom_public';
     $settings['file_private_path'] = 'custom_private';
     $settings['file_temp_path'] = 'custom_temp';
@@ -505,6 +532,19 @@ public function testEnvironmentLocal(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_LOCAL;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -519,6 +559,7 @@ public function testEnvironmentLocal(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -574,6 +615,19 @@ public function testEnvironmentLocalContainer(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_LOCAL;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -590,6 +644,7 @@ public function testEnvironmentLocalContainer(): void {
       '^example\-site\.docker\.amazee\.io$',
       '^nginx$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -687,6 +742,19 @@ public function testEnvironmentCircleCi(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_CI;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -701,6 +769,7 @@ public function testEnvironmentCircleCi(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
   // phpcs:ignore #;> SETTINGS_PROVIDER_CIRCLECI
@@ -758,6 +827,19 @@ public function testEnvironmentGha(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_CI;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -772,6 +854,7 @@ public function testEnvironmentGha(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
   // phpcs:ignore #;> SETTINGS_PROVIDER_GHA
@@ -825,6 +908,19 @@ public function testEnvironmentAcquiaDynamic(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_DEV;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -838,6 +934,7 @@ public function testEnvironmentAcquiaDynamic(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -889,6 +986,19 @@ public function testEnvironmentAcquiaDev(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_DEV;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -902,6 +1012,7 @@ public function testEnvironmentAcquiaDev(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -953,6 +1064,19 @@ public function testEnvironmentAcquiaStage(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_STAGE;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -966,6 +1090,7 @@ public function testEnvironmentAcquiaStage(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -1014,6 +1139,19 @@ public function testEnvironmentAcquiaProd(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_PROD;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -1027,6 +1165,7 @@ public function testEnvironmentAcquiaProd(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -1080,6 +1219,19 @@ public function testEnvironmentAcquiaConfigPathOverride(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_DEV;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -1092,6 +1244,7 @@ public function testEnvironmentAcquiaConfigPathOverride(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -1153,6 +1306,19 @@ public function testEnvironmentAcquiaConfigVcsDirectoryFallback(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_DEV;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -1165,6 +1331,7 @@ public function testEnvironmentAcquiaConfigVcsDirectoryFallback(): void {
     $settings['trusted_host_patterns'] = [
       '^localhost$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -1224,6 +1391,19 @@ public function testEnvironmentLagoonPreview(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_DEV;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -1242,6 +1422,7 @@ public function testEnvironmentLagoonPreview(): void {
       '^example1\.com$',
       '^example2$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -1299,6 +1480,19 @@ public function testEnvironmentLagoonDev(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_DEV;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -1317,6 +1511,7 @@ public function testEnvironmentLagoonDev(): void {
       '^example1\.com$',
       '^example2$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -1374,6 +1569,19 @@ public function testEnvironmentLagoonTest(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_STAGE;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -1392,6 +1600,7 @@ public function testEnvironmentLagoonTest(): void {
       '^example1\.com$',
       '^example2$',
     ];
+
     $this->assertSettings($settings);
   }
 
@@ -1447,6 +1656,19 @@ public function testEnvironmentLagoonProd(): void {
     $settings['container_yamls'][0] = $this->app_root . '/' . $this->site_path . '/services.yml';
     $settings['entity_update_batch_size'] = 50;
     $settings['environment'] = self::ENVIRONMENT_PROD;
+    // phpcs:ignore #;< MODULE_FAST_404
+    $settings['fast404_allow_anon_imagecache'] = TRUE;
+    $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+    $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
+    $settings['fast404_whitelist'] = [
+      'index.php',
+      'rss.xml',
+      'install.php',
+      'cron.php',
+      'update.php',
+      'xmlrpc.php',
+    ];
+    // phpcs:ignore #;> MODULE_FAST_404
     $settings['file_public_path'] = 'sites/default/files';
     $settings['file_private_path'] = 'sites/default/files/private';
     $settings['file_temp_path'] = '/tmp';
@@ -1465,6 +1687,7 @@ public function testEnvironmentLagoonProd(): void {
       '^example1\.com$',
       '^example2$',
     ];
+
     $this->assertSettings($settings);
   }
 
diff --git a/tests/phpunit/Drupal/SettingsTestCase.php b/tests/phpunit/Drupal/SettingsTestCase.php
index 4e4bfedd29..28e0cb388a 100644
--- a/tests/phpunit/Drupal/SettingsTestCase.php
+++ b/tests/phpunit/Drupal/SettingsTestCase.php
@@ -212,6 +212,47 @@ protected function requireSettingsFile(array $pre_settings = [], array $pre_conf
     $this->databases = $databases;
   }
 
+  /**
+   * Require a per-module settings file with an explicit contrib path.
+   *
+   * Per-module settings files guarded by the presence of a module directory
+   * are unreachable through the site's own contrib path when the module is not
+   * required by the project.
+   *
+   * @param string $module
+   *   Module name as it appears in the `settings.<module>.php` file name.
+   * @param string $contrib_path
+   *   Path to the contrib modules directory to expose to the settings file.
+   * @param array $pre_settings
+   *   Array of settings to pre-populate.
+   * @param array $pre_config
+   *   Array of configs to pre-populate.
+   */
+  protected function requireModuleSettingsFile(string $module, string $contrib_path, array $pre_settings = [], array $pre_config = []): void {
+    $app_root = getcwd() . '/web';
+
+    if (!file_exists($app_root)) {
+      throw new \RuntimeException('Could not determine application root.');
+    }
+
+    $site_path = 'sites/default';
+    $file = implode(DIRECTORY_SEPARATOR, [$app_root, $site_path, 'includes', 'modules', sprintf('settings.%s.php', $module)]);
+
+    if (!file_exists($file)) {
+      throw new \RuntimeException(sprintf('Settings file %s does not exist.', $file));
+    }
+
+    $config = $pre_config;
+    $settings = $pre_settings;
+
+    require $file;
+
+    $this->app_root = $app_root;
+    $this->site_path = $site_path;
+    $this->config = $config;
+    $this->settings = $settings;
+  }
+
   /**
    * Assert that config retrieved from the real settings file match test data.
    *
diff --git a/tests/phpunit/Drupal/SwitchableSettingsTest.php b/tests/phpunit/Drupal/SwitchableSettingsTest.php
index c285060b94..12f7f3a417 100644
--- a/tests/phpunit/Drupal/SwitchableSettingsTest.php
+++ b/tests/phpunit/Drupal/SwitchableSettingsTest.php
@@ -4,6 +4,10 @@
 
 namespace Drupal;
 
+// phpcs:ignore #;< MODULE_FAST_404
+use PHPUnit\Framework\Attributes\PreserveGlobalState;
+use PHPUnit\Framework\Attributes\RunInSeparateProcess;
+// phpcs:ignore #;> MODULE_FAST_404
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\Attributes\Group;
 
@@ -19,6 +23,25 @@
 #[Group('drupal_settings')]
 class SwitchableSettingsTest extends SettingsTestCase {
 
+  // phpcs:ignore #;< MODULE_FAST_404
+
+  /**
+   * Path to the contrib modules directory fixture.
+   */
+  protected ?string $contribFixture = NULL;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function tearDown(): void {
+    if (!is_null($this->contribFixture)) {
+      $this->removeContribFixture($this->contribFixture);
+    }
+
+    parent::tearDown();
+  }
+
+  // phpcs:ignore #;> MODULE_FAST_404
   // phpcs:ignore #;< SERVICE_CLAMAV
 
   /**
@@ -232,6 +255,106 @@ public static function dataProviderEnvironmentIndicator(): \Iterator {
   }
 
   // phpcs:ignore #;> MODULE_ENVIRONMENT_INDICATOR
+  // phpcs:ignore #;< MODULE_FAST_404
+
+  /**
+   * Test Fast 404 settings.
+   *
+   * Runs isolated so that the module stub owns the 'fast404_preboot()'
+   * declaration and its invocation marker is conclusive.
+   */
+  #[DataProvider('dataProviderFast404')]
+  #[RunInSeparateProcess]
+  #[PreserveGlobalState(FALSE)]
+  public function testFast404(bool $module_installed, array $expected_present, array $expected_absent = []): void {
+    $contrib_path = $this->createContribFixture($module_installed);
+
+    $this->requireModuleSettingsFile('fast_404', $contrib_path);
+
+    $this->assertSettingsContains($expected_present);
+    $this->assertSettingsNotContains($expected_absent);
+    $this->assertSame($module_installed, file_exists($contrib_path . '/fast_404/preboot'), 'Preboot invocation');
+  }
+
+  /**
+   * Data provider for testFast404().
+   */
+  public static function dataProviderFast404(): \Iterator {
+    yield 'module installed' => [
+      TRUE,
+      [
+        'fast404_exts' => '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i',
+        'fast404_allow_anon_imagecache' => TRUE,
+        'fast404_whitelist' => ['index.php', 'rss.xml', 'install.php', 'cron.php', 'update.php', 'xmlrpc.php'],
+        'fast404_html' => '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>',
+      ],
+    ];
+    yield 'module not installed' => [
+      FALSE,
+      [],
+      [
+        'fast404_exts' => NULL,
+        'fast404_allow_anon_imagecache' => NULL,
+        'fast404_whitelist' => NULL,
+        'fast404_html' => NULL,
+      ],
+    ];
+  }
+
+  /**
+   * Create a contrib modules directory fixture.
+   *
+   * The Fast 404 module is not required by the project, so its settings file
+   * guard can only be satisfied by a stub.
+   *
+   * @param bool $with_fast404
+   *   Create a stub of the Fast 404 module within the fixture. The stub marks
+   *   the directory when its preboot function is called.
+   *
+   * @return string
+   *   Path to the contrib modules directory fixture.
+   */
+  protected function createContribFixture(bool $with_fast404): string {
+    $this->contribFixture = getcwd() . '/.artifacts/tmp/' . uniqid('contrib-');
+
+    mkdir($this->contribFixture, 0777, TRUE);
+
+    if ($with_fast404) {
+      $stub = <<<'PHP'
+        <?php
+
+        function fast404_preboot(array $settings = []): void {
+          touch(__DIR__ . '/preboot');
+        }
+
+        PHP;
+
+      mkdir($this->contribFixture . '/fast_404');
+      file_put_contents($this->contribFixture . '/fast_404/fast404.inc', $stub);
+    }
+
+    return $this->contribFixture;
+  }
+
+  /**
+   * Remove the contrib modules directory fixture.
+   *
+   * @param string $path
+   *   Path to the contrib modules directory fixture.
+   */
+  protected function removeContribFixture(string $path): void {
+    foreach (glob($path . '/*/*') ?: [] as $file) {
+      unlink($file);
+    }
+
+    foreach (glob($path . '/*', GLOB_ONLYDIR) ?: [] as $dir) {
+      rmdir($dir);
+    }
+
+    rmdir($path);
+  }
+
+  // phpcs:ignore #;> MODULE_FAST_404
   // phpcs:ignore #;< SERVICE_REDIS
 
   /**
diff --git a/web/sites/default/includes/modules/settings.fast404.php b/web/sites/default/includes/modules/settings.fast_404.php
similarity index 65%
rename from web/sites/default/includes/modules/settings.fast404.php
rename to web/sites/default/includes/modules/settings.fast_404.php
index 148f7d255f..d5fcf8950d 100644
--- a/web/sites/default/includes/modules/settings.fast404.php
+++ b/web/sites/default/includes/modules/settings.fast_404.php
@@ -7,9 +7,8 @@
 
 declare(strict_types=1);
 
-if (file_exists($contrib_path . '/fast404/fast404.inc')) {
-  // @codeCoverageIgnoreStart
-  $settings['fast404_exts'] = '/^(?!robots).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
+if (file_exists($contrib_path . '/fast_404/fast404.inc')) {
+  $settings['fast404_exts'] = '/^(?!\/robots)^(?!\/system\/files).*\.(txt|png|gif|jpe?g|css|js|ico|swf|flv|cgi|bat|pl|dll|exe|asp)$/i';
   $settings['fast404_allow_anon_imagecache'] = TRUE;
   $settings['fast404_whitelist'] = [
     'index.php',
@@ -19,10 +18,8 @@
     'update.php',
     'xmlrpc.php',
   ];
-  $settings['fast404_string_whitelisting'] = ['/advagg_'];
   $settings['fast404_html'] = '<!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN" "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd"><html xmlns="http://www.w3.org/1999/xhtml"><head><title>404 Not Found</title></head><body><h1>Not Found</h1><p>The requested URL "@path" was not found on this server.</p></body></html>';
-  include_once $contrib_path . '/fast404/fast404.inc';
+  include_once $contrib_path . '/fast_404/fast404.inc';
   // @phpstan-ignore-next-line
   fast404_preboot($settings);
-  // @codeCoverageIgnoreEnd
 }