JAMs Linux - Proton Mode — JAMs Steam update #1301174

Okay after learning that some prefer how Steam handles Windows apps under Proton under Linux, I wanted to have that as an available option for Linux. So you will now find that as a launch option when starting the game. It's a launch script for that Proton Mode, and after installing a whole bunch of Proton versions to test them out I realized how quickly you can run out of hard drive space doing that. I moved my Proton versions to a second hard drive, only for it to no longer detect it in my script... So I made an interactive Proton Setup script you can now use to configure your system. You don't have to be too specific when specifying the mount point of your Proton installations, the script is fairly robust to figure it out (let me know if you run into any edge-cases). You can specify your preferred version, or leave it blank and it will prefer Experimental. But for whatever reason if yo...