https://bugs.winehq.org/show_bug.cgi?id=56447
--- Comment #1 from Chiitoo chiitoo@gentoo.org --- DodoGTA on IRC asked about running with an older Mesa version, and indeed, those errs do not show up with 24.0.9, but seem to already be there with 24.1.3.
That said, I don't know how I initially missed it, but they happen when closing the application, not when starting it, which is where the splashing happens...