https://bugs.freedesktop.org/show_bug.cgi?id=107261
--- Comment #7 from Ian imyxhuang@gmail.com --- I've noticed that I can deterministically create these error messages upon locking my screen and thus allowing my monitor to go into power-save mode.
Sometimes, my resolution also goes to 1024×768 on wake, which is irreversible unless I reboot. Not sure if that's related to this bug.
Oh, and of course, both of the above are on Wayland only.