Thank you. I’ll try to reproduce it and work on a fix!
One way to address it for you now could be to temporary set your screen resolution to a normal 16:9 view, load the game, close the dialog and go into the settings to change from Fullscreen to windowed mode. Then you should be able to close the game and change your resolution back to 5120x1440 and still play the game in a 16x9 window.