It can be duplicated over and over but the bug "just" prevents you from logging into your "favorite world" and all of my worlds can be opened. But the bug prevents also from playing into copies of your worlds. So in turn it's just useless. Every other world just run fine. Even other worlds that are opened in 1.16.100.60 and 1.16.200.51 beta. I tried removing everything but still there. PLEASE FIX THIS.