ok I installed gamescope, and set my launch options (for Deus Ex)
gamescope -w 3840 -h 2160 -W 2560 -H 1440 -b -- %command%
It seems like it sorta works, Kentie's Launcher is big (like when I tried this in Bazzite's Gaming Mode), and the 3840x2160 resolution is an available option, but when I try to launch the game and Kentie's Launcher closes to launch the game, gamescope just dies and the game never starts
EDIT: I have a workaround by just skipping the config dialog
gamescope -w 3840 -h 2160 -W 2560 -H 1440 -b -- %command% -skipdialog
But OBS is only capturing at 2560x1440, so this idea doesn't work
