I use GNOME with Firefox Wayland, and I've always had it have trouble with my 200% HiDPI scaling, but with upgrade to Firefox 92, it became worse.
Before it was mostly just what seems described as bug 1708924, but after the upgrade, it goes spinning the CPU each time I switch to a workspace that has any Firefox windows, freezing all Firefox windows for 5+ seconds until it seemingly figures out the DPI situation - sometimes I visually see it drawing without the scaling instead to the top left quarter of the screen, with some visual blinking between that and slightly smaller or larger display area.
Once it settles and I can use Firefox again after 5-15 seconds, it has a tendency to misunderstand the window borders, so if I drag select any text from the bottom half of the monitor (Firefox is maximized) and go down a bit, it starts quickly scrolling the whole page, instead of just selecting where I dragged, because it seems to think I've hit the window border and behaves as such. That doesn't happen then if I keep the mouse on the top half of the monitor while doing this. This part doesn't happen always, but often.
So it feels like something gets thoroughly confused about HiDPI after workspace switches (or firefox become the active window because of that?), while before v92 it just confused after monitors changed events from them waking up after DPMS sleep.
To try to get rid of the problem, I've upgraded from gnome-shell-3.38 to gnome-shell-40.4 and after that didn't help at all, I disabled webrender compositing. This initially seemed to help for a bit, but it just needed some time to start being confused after Firefox restart.
After I started forcing GDK_BACKEND=x11, I'm "free" of these issues.