Hm, nope, no donut for me. Still gray. Tried different Proton(s) too.Disabling compatibility (Proton) in game properties fixed it for me
There might be a system update available that could fix this issue. Go to the settings on your Steam Deck, check for system updates, and install them if available.
or
you can try verifying the integrity of the game's files on Steam. This can be done by right-clicking the game in your Steam library, choosing 'Properties', going to 'Local Files', and then clicking 'Verify Integrity of Game Files'. This process will check for any missing or corrupted files and replace them.