They probably talk about the Steam Linux Runtime (or it's predecessor), which is called scout and is based on Debian 10. They also have a more recent one called

They probably talk about the Steam Linux Runtime (or it's predecessor), which is called scout and is based on Debian 10. They also have a more recent one called soldier used for proton and are working on a successor for scout called sniper (all TF2 characters). As far as I understand correctly SteamOS might be based on Arch, but it uses Valve's kernel and mesa while running the games themselves in a container. https://gitlab.steamos.cloud/steamrt/steam-runtime-tools/-/blob/main/docs/container-runtime.md https://gitlab.steamos.cloud/steamrt/steam-runtime-tools/-/b...