Valve released the latest update to Proton Experimental to bring more fixes for running Windows games on Linux / SteamOS systems.
Proton Experimental is like their testing ground for future stable numbered version Proton updates (like the upcoming Proton 11 that's currently in Beta). You can install any version of Proton by just searching for "Proton" in your Steam Library. If you already have them installed, they will just show up as updates in your Steam Downloads. Check out the recently updated GamingOnLinux Guide to all the different Proton versions.
The Proton Experimental update for May 20th includes all these changes:
- All changes from Proton 11.0-beta5.
- Now playable: Otherworld Legends 战魂铭人
- Fixed KeepUp Survival having bad performance and crashing on non-Nvidia GPU.
- Fixed Worms Armageddon ignoring system locale when suggesting language upon team creation.
- Enabled Xalia for Batman: Arkham City GOTY's settings window.
- Fixed Forza Horizon 4 and 5 showing black screen on SteamOS beta.
- Fixed Forza Horizon 6 showing black screen on desktops and SteamOS Beta.
- Fixed Proton 11 regressions:
- Fixed Source SDK 2007 and Source SDK 2013 Singleplayer failing to find gameinfo.txt.

Pictured - Forza Horizon 6 on Fedora KDE 44
Source: Changelog
You can see my initial thoughts on Forza Horizon 6 running on Desktop Linux and Steam Deck in the previous GamingOnLinux article. If you missed it - the developer of VKD3D-Proton also mentioned how Forza Horizon 6 needed some pretty "horrible" workarounds on Linux.




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