Download the .tar.xz file, unpack it, copy/move the folder "GE-Proton8-4-Dualsense" to ~/.steam/root/compatibilitytools.d and select it as compatibility tool in Steam.
Download the .tar.xz file, unpack it, copy/move the folder "GE-Proton8-4-Dualsense" to ~/.steam/root/compatibilitytools.d and select it as compatibility tool in Steam.