@benedikt reported some issues with #xwaylandvideobridge and #phosh and it turned out it uses _NET_WM_WINDOW_OPACITY which was proposed > 2️⃣ 0️⃣ years ago to be added to the wm-spec (https://lists.freedesktop.org/archives/xdg/2003-December/001413.html) but never landed although Qt, GTK and others use (or used) it.

That just changed (https://gitlab.freedesktop.org/xdg/xdg-specs/-/merge_requests/97) and we also already have #wlroots support now too so phosh can happily use it too.

But maybe I'm the only person that finds this kind of archeology exciting 🙃 .