About This File
The small patcher forces the game to use the desktop resolution, removing the black bars at 21:9. Disregard the resolution shown in the settings after patching.
Partial UI cropping is a known issue typical to Unity games but the game appears to be fully playable at 21:9 despite the barely visible health bar. Wider resolutions would likely cause important elements to disappear altogether.
Tested the latest GOG version at 2560x1080.