Don't know actually!

But after it was working on Windows, I tried it on Crossover and found that MacOS doesn't allow you to pin to one CPU. So it needed a racey scheduler rewriting.

There was also a difference in the way wine provides printer drivers that caused a buggy code path to run in the game, which caused a crash on the Steam Deck too.

So those bugs would have been critical even if the display implementation had worked.

The patch also adds an OpenGL window & scaling filter as the game's primary output, so it doesn't rely on GDI for pixel output any more.