SteamOS 3.8.3 Beta gets ready for the Steam Machine and Steam Controller

Valve released SteamOS 3.8.3 Beta which includes a bunch of bug fixes, along with more prep work for the upcoming Steam Machine and Steam Controller.

Before getting into the meat of that, there's also a new stable release with SteamOS 3.7.22 that simply notes "Security and stability updates". As for SteamOS 3.8.3 Beta, you can opt in to test it via Settings > System > System Update Channel. Here's the new bits from the update in the changelog below:

• Fixed a regression causing the Steam on-screen keyboard in desktop mode to produce the wrong keys in certain IME modes.
• Substantially improved speed of future OS updates on high-speed connections.
• Added missing graphics features needed for titles such as "Crimson Desert".
• Fixed a regression causing crashes in certain titles (such as "Sushi Ben").
• Fixed multiple regressions causing crashes in desktop mode.
• Fixed a regression causing the Steam overlay to malfunction while streaming.
• Fixed spurious wake-ups when using a Logitech Bolt receiver.
• Improved support for upcoming Steam Controller hardware.
• Even more support for upcoming Steam Machine hardware.
• Even more security and stability updates.

There was also a Steam Deck Beta Client update for April 30th with these changes:

General

• Added setting to enable or disable controller connect/disconnect notifications.
• Fixed issue that could cause three controller connect/disconnect notifications at startup

Plus all the other updates from the initial SteamOS 3.8 Beta:

General

• Fixed a case where WiFi performance could become degraded until the device was put to sleep or manually reconnected
• Fixed excessive trackpad sensitivity on certain early Steam Deck LCD models
• Initial support for upcoming Steam Machine hardware
• Updated Arch system base
• Updated graphics driver with performance and stability fixes
• Fixed a case where per-app performance settings would intermittently fail to apply when launching a game
• Improved support for the screencasts in Game Mode (e.g. OBS/Discord)
• Fixed dropdown menus not appearing in some games
• Improved VRR frame pacing
• Fixed FSR badge remaining off in the performance overlay, even if it was actually active
• Improved support for games that attempt to open PDF files in external viewers
• Fixed an issue affecting certain titles (such as "SpongeBob SquarePants: Titans of the Tide") where the game window could have an incorrect position
• Fixed closing certain titles (such as "STAR WARS Jedi: Survivor™") and Starfield resulting in a session crash
• Improved support for certain USB racing wheels and USB devices that boot in a non-standard mode
  • Frequently these are devices that appear as USB storage devices with a driver installer, and must be switched to their normal mode by the OS
• Steam Deck controller firmware updates now display update progress on the splash screen
• Fixes issue on specific Steam Deck revisions where firmware updates could render the left controller inoperative for that session
• Numerous stability and security updates

Bluetooth

• Re-re-enable Bluetooth Wake for Steam Deck LCD
  • Fix for more spurious wake issues that were present in earlier attempts

Audio

• Detect HDMI channel count and expose surround configuration if available
• Add a setting to allow using Bluetooth headset mics (Bluetooth playback quality will be worse while capture is active)
• Restore internal audio device on reboot if set to "Off" in desktop mode
• Increase suspend timeout for HDMI devices so initial audio isn't cut off after a few seconds of inactivity
• Fixed a bug with switching input devices when a wired headset is plugged in
• Fixed an issue where audio underruns could be experienced after sleep/resume

Accessibility

• Added an option to force mono audio output

Desktop Mode

• KDE Plasma updated to version 6.4.3 from 6.2.5, and now uses wayland by default
  • Fixes several cases of reduced performance in Desktop Mode compared to Game Mode
  • Improved support for rotated displays
  • Better scale factor out of the box on TVs
  • Adds support for external HDR displays
  • Adds support for VRR displays
  • Adds support per-display scale factor
  • For more information, see Plasma release announcements
    • https://kde.org/announcements/plasma/6/6.3.0/
    • https://kde.org/announcements/plasma/6/6.4.0/
• Keyboard layout and language are now obeying Game Mode settings
• Improved windowing behavior for games running in Proton

System Firmware

• Includes Steam Deck LCD BIOS v133
  • Security updates
  • Added "Memory Power Down" setup option
  • Preliminary support for hibernation
• Includes Steam Deck OLED BIOS v114
  • Security updates
  • Charging LED now changes color when charge limit is reached, rather than only at 100%

Non-Deck

• Improved compatibility with recent Intel and AMD platforms
• Greatly improved video memory management with discrete GPU platforms
• Fixed a compatibility issue with the SteamOS chainloader that could cause a boot failure on some desktop systems with recent UEFI firmware
• Power button short and long presses now supported across a wide variety of devices
• Improved controller support for OneXPlayer F1 series, GPD Win 5, GPD Win Mini, Anbernic Win600, OrangePi NEO, and Lenovo Legion Go
• Added controller support for OneXPlayer X1 series and Lenovo Legion Go 2
• Added system and controller firmware update support for the Lenovo Legion Go 2
• Added preliminary charge limiting support for Legion Go, Legion Go S, and Legion Go 2 - currently only accessible in Desktop Mode
• Added controller RGB LED color settings for the Lenovo Legion Go 2
• Added controller, TDP control, and speaker audio support for the ASUS ROG Xbox Ally series
• Reduced handheld controller input latency from 5-8ms to 100-500us
• Night mode, color vibrance, and color temperature sliders in Steam now work on Z2E and later AMD APUs
• Seamless boot fixes for Z2E and later AMD APUs
• Automatically handle internally rotated display for some third-party handhelds
• Improved motion control support for handhelds with BMI260 IMUs
• SD card reliability improvements for some third-party handhelds, including ASUS ROG Xbox Ally, Legion Go 1, Legion Go S, Legion Go 2, and MSI Claw
• Fixed washed out colors for Zotac and OneXPlayer handhelds with OLED
• Fixed some GPU hangs on Phoenix APU devices (Tales of Arise, Octopath Traveler II)
• Fixed ASUS ROG Ally power consumption from fingerprint reader while shut down
• Fixed trackpad losing functionality after sleep/resume on the Legion Go

Developer

• Desktop Mode now uses Wayland by default
  • X11 support may still be selected via Steam developer settings, or via `steamosctl`
• Updated Linux kernel to 6.16
• Steam now uses steamos-manager to query available desktop sessions and trigger desktop session switching
• Added support for setting the desktop password in developer settings
• Initial support for running as a Virtual Machine guest (virtio guest drivers)
• Added support for third-party devices to trigger the SteamOS boot menu via EFI variable
• Added `custom-update` verb to `atomupd-manager` for easier testing of specific builds
• System reports now include more audio debug information
• Initial support for LAVD CPU scheduler via `steamosctl set-cpu-scheduler lavd`