GNOME-Shell & budgie-desktop application focus is back to front
Edit: I've reproduced the issue below with GNOME-Shell + Plank (Ubuntu 19.10 with mutter v3.33.91 - using the GNOME + Xorg session i.e. vanilla gnome shell
So with any dock like plank it is very confused as to what window has application focus - it thinks the previously focused window is the focused window. This makes using the dock very weird indeed.
I am using budgie desktop on 19.10 ubuntu eoan that is currently compiled with v3.33.91 mutter.
Budgie Desktop is essentially a mutter plugin.
Reported by users is that apps like plank and budgie's icon tasklist applet shows the focus of applications for the previous application window ie. if you open a terminal, then open a file-manager (i.e. now has focus) - the budgie applet shows the focus as being the terminal, and plank is totally confused which app it is trying to focus/minimise etc.
I've pinned this down to a specific commit made early in the mutter 3.33 development cycle
What I don't really understand is why we are seeing "back-to-front" focused windows. I don't really see anything in the budgie desktop code base that uses any of the functions mentioned in that commit.
The bit in budgie I believe interfaces directly with mutter is this bit https://github.com/solus-project/budgie-desktop/blob/master/src/wm/wm.vala
Any hints on what I should really looking for that was impacted by that commit & possibly what areas that could be problematic would be gratefully received!