https://gitlab.gnome.org/GNOME/mutter/-/issues/4342, https://gitlab.gnome.org/GNOME/mutter/-/issues/4310.

Preconditions:

• gnome-shell 49.0-1 from Debian experimental (upstream 49.0 + minor patches) in Wayland mode
  • using mutter libraries 49.0-2 from Debian experimental (upstream 49.0 + minor patches)
• SDL 3.3 snapshot from 2025-09-03 (probably 4441d8b, or if not that then some nearby commit)
• sdl2-compat snapshot from 2025-09-10
• OpenArena running on ioquake3 engine snapshot from 2025-09-08, configured for r_fullscreen 1 and r_mode -2 ("borderless window", copying the resolution/mode that the screen is already configured for)

In this situation, running openarena crashes the compositor. This is a compositor bug hopefully fixed in libmutter by https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/4648 (SDL shouldn't be able to crash the compositor even if it wanted to), but mutter upstream's analysis indicates that SDL is reporting out-of-spec window geometry to the compositor, which would be a client bug. After applying the merge request, I believe the intention is that gnome-shell will log a warning rather than crashing (not yet tested, the patched mutter is still compiling).

Things that do not crash: SDL_VIDEO_DRIVER=x11 openarena, or forcing the use of "classic" SDL2 via SDL_DYNAMIC_API (with either X11 or Wayland, both work).

I haven't confirmed whether SDL main still has this, but there's no obvious fix in the git history. I also haven't confirmed whether 3.2 has this.