Currently working on automating some light/dark theme changes on Linux, but in a WM environment (so no Gnome settings, etc.). Came across this on the Arch wiki,

Currently working on automating some light/dark theme changes on Linux, but in a WM environment (so no Gnome settings, etc.). Came across this on the Arch wiki, of course, and looks useful. Unfortunately there's a lot of different applications and ui toolkits to deal with.... Will probably write up a little guide with what I find once I have it set up, at least for firefox/gtk with darkman, xsettings.