So last week I posted a video of Forza Horizon 4, running on Fedora 34 in Steam Play/proton, at 4k Ultra with resizable bar enabled.For reference, the 4k 60 ultra resizable bar video can be found here:https://www.youtube.com/watch?v=xpu2b8nIxIY&lcThis time, we now -also- have an FSR patch set (AMD Fidelity Super Resolution) which works alongside proton's fullscreen hack.Proton's fullscreeen hack is a modification to proton which allows displaying smaller or non-standard resolutions within your monitor's default resolution without changing it. Essentially it's capable of doing what FSR does -- scaling up smaller resolutions. However now that FSR has been released, that hack has been retro-fitted using FSR for it's upscaling backend. Meaning yes -- FSR can be used on almost any game running in proton. There are a few limitations, for example some games which already have FSR or other scaling implementation may not work.So the way this works is -- the FSR resolutions are patched in alongside FSR for the upscaling backend. Since the fullscreen hack already attempts to upscale, all you have to do is set the game's resolution to a lower resolution, preferably one of the FSR resolutions:FSR Preset Scale Factor 4K Input 1440p Input 1080p InputUltra Quality 1.3X 2954x1662 1970x1108 1477x831Quality 1.5X 2560x1440 1706x960 1280x720Balanced 1.7X 2259x1270 1506x847 1130x635Performance 2.0X 1920x1080 1280x720 960x540There is even an additional variable so that you can fine tune the sharpening used in the patch set. Anyway, so what I've done here is added the patches for both FSR with fullscreen hack and resizable bar, then set my resolution to 2954x1662 in game, since my monitor is running at 4k, that way the fullscreen hack utilizes FSR to upscale. The rest of the in-game settings are all set to ultra, and the end result is another 25 fps boost on top of the 133 fps that resizable bar alone was giving us, totaling about 160 fps