https://bugs.winehq.org/show_bug.cgi?id=50859
--- Comment #7 from Rafał Mużyło galtgendo@o2.pl --- (In reply to Zebediah Figura from comment #4)
Okay, according to the linked bug report it's a Mesa bug.
...no ? At least mesa devs don't seem to think so. According to mesa bug, it's a matter of mesa applying certain checks more consistently (https://gitlab.freedesktop.org/mesa/mesa/-/issues/3969).
If I'm reading it correctly, the change was to make mesa emit an error if glXCreateContextAttribsARB returned NULL even if it wasn't a server-side failure and clean up the context.