Note: This update is for the Steam Deck Preview channel, and includes new features that are still being tested. You can opt into this in Settings > System > System Update Channel.
Note on Preview Releases
This is an early Preview build of SteamOS 3.9, and may contain unexpected bugs or stability issues. If you encounter problems, please consider filing a bug on the SteamOS issue tracker.
These notes contain all changes since the current stable SteamOS 3.8 release, with the changes added since the previous preview noted below
New in SteamOS 3.9.1
General
Fixed a system crash when launching Forza Horizon 6 on Legion Go 2
Fixed an issue causing frame limits to result in lower than intended FPS on certain external displays
Fixed issues with suspend/resume on systems with RDNA1 or RDNA2 based dedicated GPUs
Fixed a regression in seamless boot causing the boot logo to disappear prior to the Steam startup animation
Fixed a rare issue where fan speed would revert to BIOS control until a reboot, resulting in higher than normal fan speeds on Steam Deck
Security and stability updates
Developer
Fixed verbose-mode boots, triggered by the [c]steamos-bootdebug[/c] utility or chainloader menu, having their output hidden by plymouth
Updated included renderdoc version
SteamOS 3.9
General
Misc
Developer
Switched WiFi backend to wpa_supplicant by default for new installations, improving compatibility with various WiFi networks
Enhanced wpa_supplicant to support fast WiFi reconnect on resume from sleep, previously only available in the iwd backend
Known issue: Existing installations will continue to use iwd unless manually enabled in Developer Settings
Linux kernel rebased on Linux 7.2
Added preliminary support for hibernation, not yet exposed in Game Mode UI
Various scripts and packages have been renamed from `steamos-` to `holo-`, with aliases to the former names where appropriate
Improved support for running SteamOS as a VM guest with accelerated graphics (virtio-gpu, venus)