- Previously playable only with Proton Experimental: Sonic Colors: Ultimate, Command & Conquer: Red Alert 2 and Yuri’s Revenge, Command & Conquer Tiberian Sun and Firestorm, Aisling and the Tavern of Elves, Snares of Ruin 2, Insanity's Blade, Bloody Walls.
- Fixed Proton 9.0 regressions:
- Overwatch 2 no longer randomly crashes.
- Video playback in Age of Empires II: Definitive Edition works again.
- Total War: WARHAMMER II no longer has clicking audio while playing videos.
- Call of Juarez: Gunslinger no longer crashes on start.
- Sea of Thieves is able to play videos on Steam Deck.
- Borderlands GOTY Enhanced is playable again.
- Mars First Logistics is now able to upload to Steam Workshop.
- Neverwinter, Star Trek Online and Champions Online are playable again on Nvidia setups.
- Fixed input issues with Worms Armageddon.
- Main menu video is looping correctly in Call of Cthulhu.
- Fixed audio in BOOMEROAD, DORONKO WANKO, NOTTOLOT.
- Fixed Civilization V Touch Only option in the launcher not working.
- Improved cutscene desync in Immortals Fenyx Rising.
- Limited number of cores seen by the following games making them playable on a high core count CPUs:
- Far Cry 2
- Far Cry 4
- The Witcher 2: Assassins of Kings Enhanced Edition
- Lara Croft and the Guardian of Light
- Warhammer 40,000: Space Marine
- Warhammer 40,000: Dawn of War II
- Warhammer 40,000: Dawn of War II - Chaos Rising
- Warhammer 40,000: Dawn of War II - Retribution
- Outcast - Second Contact
- Prototype