Valve has released SteamOS 3.5.14 Preview for Steam Deck, which comes with performance improvements for the new Persona 3 Reload amongst other things.
Since it's currently in Preview if you wish to try it you need to go into the System settings, and change the System Update Channel to Preview in the drop-down box. Here's what's changed (changelog):
- Improved performance of ray-traced reflections in Persona 3 Reload.
- Slightly improved corner tracking on Steam Deck OLED trackpads.
- Fixed a possible session crash when connecting an HDR display.
- Fixed a rare session crash on application exit.
Don't go expecting some kind of miracle though, ray tracing on Steam Deck is pretty tough.
Additionally a Steam Deck Beta update was also released with these changes (changelog):
- Fixed misc. regressions in the screenshot manager.
- Fixed transparency and blur on header and app details play bar.
- Fixed graph height on downloads page.
- Fixed wide game images sometimes failing to load.
- Fix custom logo positions sometimes not applying on app details pages.