Steam Deck will run native Linux games where it makes sense

Valve has clarified that when it comes to which version of a game to run on the Steam Deck, the native Linux incarnation will be used – rather than the Windows game via Proton – if it makes sense to do so. In other words, if the native Linux port runs fine.

There was some confusion around this because some eagle-eyed folks had spotted that Portal 2, one of Valve’s own games that has been ported to Linux, was down in SteamDB as being recommended to run on the Steam Deck via Proton (meaning the Windows version, facilitated by the compatibility layer, Proton, to run on SteamOS which is, of course, a Linux-based operating system).

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