Valve shipped a hefty Steam Client Beta on September 9, 2026, that noticeably upgrades Big Picture Mode and SteamOS on the Steam Deck. Alongside new visual features, the Proton selection that sits at the heart of Linux gaming becomes much tidier.
Big Art Mode and a new screensaver
For Big Picture Mode on desktop Linux and SteamOS, Valve adds a new “Big Art Mode” under Settings > Home that puts game artwork front and center, replacing third-party plugins some users relied on. A new screensaver under Settings > Customization defaults to an artwork slideshow drawn from recently played titles and your own screenshots, with an optional retro-style bouncing logo. Users can drop custom screensavers into the Steam config directory.
A cleaner Proton picker
The compatibility-tool dropdown has been reworked: very old Proton versions are now hidden by default and can be unhidden on demand. Valve also introduces aliases such as “Proton Stable” so players automatically follow the current stable build. A bug that showed Windows games as “Not Compatible” until a Proton version was manually selected has been fixed.
Desktop mode via a toggle
SteamOS gains a “Default to Desktop Mode” toggle in system settings. New confirmation dialogs appear when leaving VR or switching to desktop mode, and the device now notifies you which user is active when waking from sleep if several accounts were recently used.
Source: GamingOnLinux, citing the official Steam Client Beta changelogs of September 9, 2026.
