Only present in the native version of the game. Black replaces several otherwise transparent textures.
Input issues were only present on the native version of the game. You cannot turn indefinitely in either direction; you will stop. Also, you cannot look down until you have looked all the way up. These issues were present even on controller.
On the native version of the game, clicking on the white door in the menu leaves a black screen. I was only able to play by clicking on the book.
Along with issues, there is a benign anomaly with input. Mouse sensitivity seems to go way up when playing the game via Proton compared to playing natively. If I had to guess, it's because the Windows version uses raw mouse input, while the Linux one uses the global cursor sensitivity. This may be a problem for you if you use high DPI on your mouse, as there's no opton to change mouse sensitivity in-game, but if you use a low or normal amount of DPI on your mouse, you'll likely be fine.
