Plasma (X11) still doesn't work when selected as kwin_x11 times out trying to use GL compositing and restarts itself without compositing, but things no longer core dump so X in general (for things that want to use Xwayland) is likely in better shape than it was. Not sure why X11 compositing isn't working, something about SYNC extension fences never getting triggered from kwin's perspective, but we don't actually need it to work.
Plasma (X11) still doesn't work when selected as kwin_x11 times out trying to use GL compositing and restarts itself without compositing, but things no longer core dump so X in general (for things that want to use Xwayland) is likely in better shape than it was. Not sure why X11 compositing isn't working, something about SYNC extension fences never getting triggered from kwin's perspective, but we don't actually need it to work.