There is a bug in practice when using special keys.

[NotAdrix]

When I link jumps with Ctrl, for example, when entering practice mode at a given moment, if I hold down the key and want to place a checkpoint at the same time, it doesn't let me until I release the Ctrl key.

[Cvolton]

currently you need to set a separate keybind for Ctrl+Z as well, we will likely be adding support for "Any modifier" keybinds in the future to fully mitigate this issue