Compatibility Report

• Name of the game with compatibility issues: Elden Ring
• Steam AppID of the game: 1245620

System Information

• GPU: RX6800XT
• Driver/LLVM version: mesa 22.2.3-1
• Kernel version: 6.0.11-arch1-1
• Link to full system information report as Gist: https://gist.github.com/RuneFFF/97caf35cdc7b11de76ac9b9bdc03c683
• Proton version: Experimental

I confirm:

• [x] that I haven't found an existing compatibility report for this game.
• [x] that I have checked whether there are updates for my system available.

Symptoms

Multiplayer can not be used. The game gives an error (Inappropriate activity detected) and restarts in offline mode.
I have talked to Bandai Namco Support. This is not a problem of me being banned. I am dual booting windows on the same system. Elden Ring can be played online on windows.
I have tried reinstalling as well as manually deleting the prefix in /compatdata. This did not help. The bleeding edge beta of proton did not help either.

Reproduction

Launch Elden Ring and get to the main menu. The game logs in, and after around 3 seconds, the mentioned error occurs.

steam-1245620.log