Hey John,
Spent many hours and surprised this issue has not come up yet but, after many removal of plugins after installing 11.20 and using a VR headset, MaxxFX is the only plugin causing an issue all by its self with showing VR working but has a black screen while in VR mode. I dont have a log.txt to send because you can hear all x plane sounds but it will show a black screen in VR mode. No other stand alone plugins cause this issue. I am also not using or have flyinside installed. Using just stock 11.20r1 x plane.