Comment # 5 on bug 1190200 from Tristan Miller

(In reply to Tristan Miller from comment #4)
> Just upgraded from openSUSE 20211008 to 20211031, which included an update
> from kernel-default 5.14.9 to 5.14.14.  The problem is now worse: the
> glitches appear even when the compositor is enabled.

Booting from the old 5.14.9 kernel doesn't work around the glitching problem,
but booting from the old read-only snapshot does.  Also, I've found that the
glitching can be avoided by running a Wayland desktop instead of X11.

(In reply to Takashi Iwai from comment #3)
> Dup of bug 1190095?

I'm not sure; the symptoms reported are similar but still different.  Bug
1190095 talks about a "slow redraw" where the screen glitches for a moment and
then fixes itself.  But in my case, I wouldn't say that the redraw is "slow";
the glitches appear instantaneously when a screen area changes (e.g., via
scrolling), and they generally persist until I force that area of the screen to
change again, at which point the glitching either changes or (if I'm lucky)
disappears.