Is there any documentation on what exactly the Sticky Keys setting in Settings -> Universal Access -> Typing Assist (AccessX) does?
What I’ve been able to figure out by playing around with it:
Super, Ctrl, Shift and Alt all seem to count as modifier keys.
Clicking a modifier key once and then clicking a non-modifier key, is the same as if you had held down the modifier, hit the non-modifier, then released the modifier. So for example I can type a capital F by clicking Shift and then f.
Double-clicking a modifier seems to keep it held down, until you single-click the same modifier again. So for example if I double-click Shift I’ll then be typing in ALL CAPS until I single-click shift again.
I’m wondering if that’s the whole story or is there more to it?
It’s great for switching applications if you find holding down modifier keys uncomfortable. Super and then Tab will switch to the previous application. Super-Super Tab will open the application switcher and hold it open, even though you don’t have a key held down, and you can use the arrow keys or Tab and then Enter to select an app or window. Unfortunately you just have to remember to hit Super again at the end, otherwise it’ll still be held down.
Changing tabs in browsers works slightly better than the app switcher does: Ctrl then Page Up or Page Down goes to the next/prev tab. Or Ctrl-Ctrl then Page Up and Down as many times as you want to get to the desired tab then hit Ctrl again to release it.