I had a quick play using default Proton in my steam app (5.0-10) and tried and stuck with Proton-6.4-GE-1
Thus far the only issue I have found is that I am unable to change and save any graphics settings but the game does start in full windowed mode using 1920 x 1080.
It works great with only a keyboard and even more fun with my wireless XBox 360 controller. I am yet to test it with my Logitech G29. Multiplayer will be tested soon but I’m happy to let you know that mods are working flawlessly.
In short it runs great in Linux using Proton and thus far having a great time playing it.