Assetto Corsa #
Assetto Corsa runs with Proton.
Content Manager #
The most commonly used method to load custom content is Content Manager.
Download the executable and place it in ~/.steam/steam/steamapps/common/assettocorsa/ as Content Manager Safe.exe.
In Steam, create the following launch-option:
'~/.steam/steam/steamapps/common/Proton - Experimental/proton' waitforexitandrun '~/.steam/steam/steamapps/common/assettocorsa/Content Manager Safe.exe'; echo %command%
Optionally replace ~/.steam/steam/steamapps/common/Proton - Experimental/proton with the path to another Proton executable.
Content #
All custom content is located in ~/.steam/steam/steamapps/common/assettocorsa/content/.