I tried again using the controller, now it doesn't seem to open or react at all when pressing the confirm button
Could you try with the keyboard? Either the arrow keys or WS/ZS should work if resolutions are being detected properly. If not, I think it's Unity.
Just opened it again after last night. When i closed it last night i had set it to windowed but could not adjust the resolution. Today it started from windowed mode and i could see the options to choose the resolution and select them now. Strange.