Actually with modern GPU driver, it's been easier than before to use resolutions like 320x240.

Heck, I can go as low as 160x100 lol. It's possible now because of GPU scaling. When you set the scaling to GPU instead of your monitor, you can actually set resolutions like 320x240/ 320x224 etc etc and monitor will think its still using native resolution because GPU does the scaling.


That being said, borderless window will have it's use because last time I tried JJ2 with latest creators update, the game CTO ed again when I alt-tabbed. It was apparently fixed in Anniversary update, but now it came back with creators update. I can't test now because I don't have JJ2 installed anymore.

The more apparent issue is that JJ2 will blackout if you alt tab, but the sounds will still play in back screen. Now the only way to fix it is by switching to window mode and then switching to fullscreen again. But if you use widescreen resolutions like 800x450, then JJ2 will refuse to turn into window mode.