SDL: Wayland-by-default in 2.0.22rc1 causes some games to regress

While testing an attempt to upgrade SDL to 2.0.22 in the Steam Runtime, I’ve found that several games unfortunately regress when switched from X11 to Wayland. The games I’m testing are proprietary, so I can’t see into their source code, but I’m opening this issue to track regressions that I’ve found.

A mitigation is that the majority of the games I’m testing have their own bundled or statically-linked copy of SDL, which they will use by default. However, they won’t get SDL bug fixes unless either: their developer updates their SDL, or users force the game to use a newer SDL via workarounds like deleting a bundled SDL or setting SDL_DYNAMIC_API. Also, SDL 2.0.22 having a behaviour change that triggers regressions seems like it’s undermining the message that upgrading SDL 2 is always a backwards-compatible thing to do.

I wonder whether it would be useful to have a “quirks” mechanism, either in Steam or in SDL, to automatically do the equivalent of SDL_VIDEODRIVER=x11 for certain games?