The X Window System and the curse of NumLock
Ordinary modifiers are normally straightforward, in that they are additional keys that are held down as you type the main key. Control, Shift, and Alt all work this way (by default). However, some modifiers are ‘sticky’, where you tap their key once to turn them on and then tap their key again to turn them off. The obvious example of this is Caps Lock (unless you turn its effects off, remapping its physical key to be, say, another Ctrl key). … ⌘ Read more