After creating world and starting a game, whole screen is just pure white screen. White is character selection screen, and then after blindly selecting any character, whole world.
Once it somehow managed to show me character selection character screen, but then world was white again. Only thing I did different was someone messaged me on steam.
It works (or doesn't, depends how you see it) with or without fullscreen.
I'll provide video when I can.
Start game on Linux. Create new world (local) with or without caves. Start game and let it load.