[rpigab]

In my experience, Steam client and most games work great on Debian and Ubuntu, but you should know for GNU/Linux systems, it's only officially supported on Ubuntu (maybe SteamOS is implicit), I can't find the information on Steam's website or support pages, but this is a response I got from Steam Support when reporting a Steam client UI bug on Debian with GNOME, a while ago.

[moltopoco]

Which is funny because Ubuntu is also the only distro that wants you to install the Steam snap instead, which is then again unsupported.