When in main menu without steam flags, prominent black borders on bottom and right side

When not forced to 1440p via steam flags UI overlays only a third of the game window, window is 1080p on 2k display, unable to change resolution or set it to windowed (game freezes for couple seconds and reverts to original settings)

When forced to 1440p when gameplay begins cursor is forced to second monitor, bringing it back to game window causes the player camera to spin uncontrollably When not forced to 1440p, whenever mouse leaves game window the game completely freezes

Frequent FPS drops

Game completely freezes after a couple minutes of gameplay