SteamOS 3.9: Valve Ships Plasma 6.7 and Linux 7.2 to Everyone
By Indie Kings | October 26, 2026
Updated October 26, 2026: Valve shipped SteamOS 3.9.5 to every user on October 23, the first stable build in the 3.9 series, with Plasma 6.7 in Desktop Mode and a Linux 7.2 kernel underneath.
Image: Valve Corporation lobby via Wikimedia Commons.
What landed and where
Per Valve's official announcement, SteamOS 3.9.5 is released for all users, and the notes span everything since the previous 3.8 stable. Per Phoronix and linuxcompatible.org, the rollout reaches the Steam Deck, Steam Machine, Steam Frame, and compatible third-party handhelds, not just the deck. It is a big release by Valve's OS standards, and much of it benefits hardware beyond the deck.
Plasma 6.7, Linux 7.2, security
Desktop Mode jumps from Plasma 6.4.3 to Plasma 6.7.3, and the kernel is rebased on Linux 7.2, per Phoronix. Steam Deck idle power consumption improves, and idle battery life gets a stated upgrade in the notes. Security-wise, the release revokes eMudhra CA certificates, tied to a late October security scandal, per linuxcompatible.org's summary. There is also support for the Steam Frame wireless adapter, an improved bootloader for certain motherboards, plus a long list of game specific fixes across the series, from Star Wars: Galactic Racer suspend resumes on Steam Machine to GPU error fixes in The Crew Motorfest.
Release at a glance
| Item | Detail |
|---|---|
| Build | SteamOS 3.9.5, first stable in the 3.9 series |
| Date | October 23, 2026 |
| Scope | Steam Deck, Steam Machine, Steam Frame, third-party handhelds |
| Arch base | Updated |
| Desktop Mode | Plasma 6.4.3 to Plasma 6.7.3 |
| Kernel | Linux 7.2 |
| Security | eMudhra CA certificates revoked |
| Highlights | Steam Frame wireless adapter support, better idle power, bootloader compatibility |
FAQ
What is SteamOS 3.9.5?
The first stable SteamOS release in the 3.9 series, shipped to all users on October 23.
Which kernel does it use?
Linux 7.2, per Phoronix.
What changed in Desktop Mode?
KDE Plasma went from 6.4.3 to 6.7.3.
Does it reach hardware beyond the deck?
Yes, Steam Machine, Steam Frame, and third-party handhelds get this release too.
Is there a security change?
The update revokes eMudhra CA certificates, per linuxcompatible.org.
Do I need to reinstall anything?
No, it is a standard OS update from Valves channels.
Bottom Line
A stable SteamOS with a fresh kernel, a new Plasma, revoked bad certificates, and Steam Frame add-on support is the quiet foundation work that makes the Steam Machine launch down the line feel less like a gamble. Expect regressions to get patched on a beta cadence, as Valve already did with the 3.9.4 beta fixes, so let the deck update itself before a long play session.
Sources
- Valve, SteamOS 3.9 announcement (Steam Deck news, official patch notes), Oct 23 2026, accessed 26 October 2026
- Phoronix (Michael Larabel): SteamOS 3.9.5 Released With Linux 7.2 Kernel, KDE Plasma 6.7, Oct 24 2026; linuxcompatible.org and PC Guide summaries
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