I'm facing an issue while running the game on Linux Mint 21.1 Cinnamon (Ubuntu 22.04 base). Namely, after updating the mesa packages to the latest stable v22.2.5 there is now a white overlay during combat-encounters, as well as a white rectangle along the top of the screen.
Everything worked just fine with the distribution's default package, version 22.0.5.
Note that toggling the hide UI removes the white overlay (and rectangle) and shows the background and character normally.