Change the screen resolution of RetroArch on a Samsung Galaxy S7

I have changed the system screen resolution of the S7 to 1440p via Android settings, but still it seems like RetroArch still thinks the resolution is set to 1080p. I have an old DOS game that runs in 800x600, and with a native res of 1440p I should in theory be able to scale the image 2x with Integer Scaling, but somehow it seems like RetroArch 1.9.0 (downloaded on the libretro page instead of Play Store) doesn’t know that I have changed the Android screen resolution to 1440p. Even by setting Scaling in RetroArch to Custom and then set a resolution of 1600x1200, I can’t see the top- and bottom of the image.

I tried the Sonic 3 AIR Android release after changing screen res to 1440p, and with Integer Scaling there I got more screen real estate compared to when running Android in 1080p because of the change in Android Screen resolution.

Any suggestions? Is this a known issue in the Android versions of RetroArch, that it doesn’t recognize the 1440p screen resolution?