Mouse cursor hidden when running fullscreen on Wayland

[blast007]

A user on the forums reported this and I was able to reproduce it as well. The user on the forum was running an AMD Radeon HD 5550 on Fedora 34. I replicated it using an AMD Radeon HD 5450 card running with Gnome on Wayland. I was using our Flatpak version of the game. Switching to Gnome on Xorg worked around the issue.

I plan to do some additional testing when I have some time. This may be a bug with the SDL2 version used with the Flatpak/Flathub runtimes.

[blast007]

This seems to affect more than just BZFlag. Even Chromium (from Flathub) has the issue when fullscreened via the F11 key or via Gnome's fullscreen key.

https://www.reddit.com/r/openSUSE/comments/n82w5g/invisible_mouse_cursor_in_fullscreen_games_under/

[blast007]

So here's the list of workarounds:

1. Run Gnome on Xorg
2. Run the game at a different resolution. Even switching to one resolution and back to native seems to fix it until you restart the client.
3. Send /localset fakecursor 1 in chat, which will enable a software-rendered cursor. This setting will not persist in the configuration file, so you'll have to run this every time you run the game.
4. Run SDL_VIDEODRIVER=wayland bzflag (or something similar for the Flatpak version), which tells SDL2 to use its Wayland driver instead of the X11 driver (which would use XWayland). This has some downsides though. At minimum, it seems you can't set the brightness (no gamma control) nor change the resolution, and the mouse cursor doesn't recenter when you respawn.

[blast007]

There's a mention that this issue has been fixed:
https://gitlab.gnome.org/GNOME/mutter/-/merge_requests/1915#note_1257437

In the reddit thread I posted earlier, there's now a mention of a Gnome extension that "disables unredirect fullscreen windows" which also supposedly fixes (or works around) the cursor issue.