I sometimes see these graphical glitches, only in Firefox, when clicking on some sort of menu. It's only on screen for about half a second (or less) and then the glitch disappears and the menu looks normal. I'm running latest instance of Ubuntu 20.04 and the latest instance of FF but this occurred in earlier builds of FF as well. Wayland, Gnome desktop. I'm running an AMD GPU, stock AMD drivers that ship/install with Ubuntu installation.
I don't see this glitch all the time and I've never seen it in other applications. Has anyone else seen this in Firefox or knows what may be the cause/resolution?
I've never used Firefox before but because of vaapi support I'm using it more often these days than other browsers.
I've included a photo which illustrates what I'm seeing. The image on the left is what a Firefox menu item might look like for a second before the 'glitch' disappears and the menu item looks normal.