bindm — modifier-only keybind that cancels if another bind combo fires

[porl]

I am trying to migrate from my current Hyprland setup, and the main thing I'm missing is being able to bind a modifier key alone to launch something like fuzzel, while still using that modifier normally in combos.

The problem:

If I have the following config options

bindr=SUPER,Super_L,spawn,fuzzel 
bind=SUPER,w,spawn,zen-browser

Then fuzzel launches even after SUPER+w because there's no way to "cancel" the modifier that was "used" for something else.

I implemented this as bindm which is a new "modifier only" on-release type that fires on modifier release, but only if no regular bind or mousebind fired during that hold.

Config syntax example:
bind=SUPER,w,spawn,firefox # normal bind for reference
bindm=SUPER,,spawn,fuzzel # only fires if no other combo hit (won't fire on SUPER+w)
bindm=SUPER+SHIFT,,spawn,wofi # mod combos work too

PR with the implementation: #911

I'm happy to adjust naming or format if you prefer something different, and used some LLM assistance as low level C is not my strong suit (but did my best to check everything).

Tested working on my setup (Arch, wlroots 0.19.3).

[porl]

PR #918 by demperor-music implements this in a cleaner way. Closing my PR but keeping this discussion open for reference.