Note: This update is for the Steam Deck Beta and Preview channels, and includes new features that are still being tested. You can opt into this in Settings > System > System Update Channel.
These notes contain all changes since the current stable SteamOS 3.7 release, with the new changes since the previous 3.8.8 Beta noted below
New in 3.8.9
Fixed a 3.8 regression where "Allow Tearing" could result in graphical artifacts beyond the expected tear line
Improved dynamic detection of HDMI audio...