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The latest SteamOS beta has been released, 3.8.25, bringing with it some new features, bug fixes and - most critically for owners of certain gaming handhelds - support for new non-Valve devices. The patch notes mention MSI Claw and OneXPlayer "device variants", with later, more specific mentions of initial controller support for the MSI Claw 8 EX AI+, Konkr Fit, Ayaneo Pocket S and OneXPlayer Apex.
There's also a fix for a long-standing issue where the Steam Machine's CPU performance would be nerfed after waking from sleep, which then required a full system reboot to clear. This was an issue reported by quite a few early customers, so it's great to see it (hopefully) gone for good.
The new version also, adorably, adds wake-on-controller support for the original Steam Controller from 2015, and makes the Steam Controller also work as a controller without Steam running - which might be useful for desktop mode shenanigans.
There's also a battery indicator that shows when you're charging your device, but currently spending more energy than you're getting - which should be a robust hint to temporarily lower your device's power usage through frame-rate caps or power management if you want it to actually recharge.
Note that if you do want to test this beta release, there's currently a compositor bug where performance is degraded with FSR and other upscalers enabled - so be aware, and be ready to roll back to the latest stable version (3.8.16) if it proves too annoying. Valve says that they're currently working on bringing the fix into the beta channel.
The full patch notes are available via the link below. Let me know if you spot any more interesting changes!