feat: add shortcut modifier side

[decodism]

My attempt at #2988.

[LiamKearn]

@decodism Thank you, I've tested locally and this is working fabulously for my use case of using rCMD+Tab for the browser.

[lwouis]

Hi @decodism,

Thank you for sharing this work!

I tested this locally, and it seems to work correctly. I also works for multiple modifiers: all of them need to be on the specified side, for the shortcut to register.

I have an issue with this though: the UX. Merging this PR would mean adding yet another dropdown menu to the preferences UI. It's already very complex and rich, and I'd like to actually decrease the number of elements shown (see #351).

Furthermore, the position of this dropdown is not very clear I think. It says modifier when there could be multiple modifiers, and it's a bit far away from the left input-box, so it could be confusing for people who set for example alt+shift with alt on the left input-box, and shift on the right input-box. They may be confused as to which modifier is referenced by the label.

Overall, i think this feature is a bit too niche to be made mainstream. I'm not sure if there is a way to have a better UX that wouldn't confuse the 99.9% of users who don't need and don't know that both sides of the keyboard can even be distinguished.

What do you think?

Thank you 🙇

[decodism]

I've made the UI more compact and made the behavior more useful by allowing another AltTab shortcut to be assigned to the unused side. I'm not so sure about the logic in case of conflict, though.

[LiamKearn]

@decodism The latest changes seem to break things for me.

When using a modifier side (L or R) windows don't focus on shortcut release (they do if I manually click them). Using "" they work once-more.

[decodism]

It's fixed. I completely missed it. Probably needs more testing.

[LiamKearn]

@lwouis RE: the UI issues, I'm guessing you're opposed to merging "defaults only" features on the grounds that it may add complexity while not getting used by enough users?

e.g. I mean features that are only exposed by documenting that you could do "defaults write etc. etc." to turn on/off xyz.

[lwouis]

Hi @LiamKearn,
Yes indeed. I'd like to avoid adding features that are only used by a few people.
Thank you