Hello @Nitrama, err:steamclient:create_win_interface Don't recognize interface name: STEAMREMOTESTORAGE_INTERFACE_VERSION016 is the line of interest in the log. That tells us the steam client bridge in Proton 5.0 is too old for this game. This isn't particularly interesting because there are updated iterations of the client bridge in newer Proton versions.
Proton 5.13 and newer is run inside of the Steam Linux Runtime - Soldier container environment. This container environment grew support to work with Flatpak, but it required some adjustments on Flatpak's side and there's some caveats noted at https://github.com/ValveSoftware/steam-runtime/blob/master/doc/steamlinuxruntime-known-issues.md#flatpak. Flatpak provided on the host system side is too old. Please retest with Steam for Linux outside of Flatpak or update Flatpak your system.
Its Working!
Thanks!
proton 5.0x1 2022-07proton 5.13x1 2022-07
Compatibility Report
System Information
I confirm:
https://gist.github.com/Nitrama/ad523e3a0d8ab29026734c155d18d8e0
Symptoms
"Not connected to Steam"
Reproduction
Start game.