Controls that are bound to an action with a + prefix (e.g. While in the menu, the 'Enter' key selects a command for adding a bound key, the 'Escape' key cancels the change, and the 'Backspace' key unbinds all keys bound to this command. Its MENUDEF name is CustomizeControls and it can be summoned with the menu_keys console command.
The customize controls menu allows to bind and unbind actions to keys and buttons from the keyboard, mouse or joystick.
