I am only having issues when a world is or has been opened to LAN (I went through several debug steps, reduced game to only vanilla no add-ons no resource packs) The worst one was a complete wipe of a LAN co-play world where it would not render for me (world saved on my device) but the LAN players could see everything (particles were still visible the rest was void like for me) in this world when I was attempting to save it the MB size of the world jumped from 32 to 5 then 3 then 5 then it went to 1.2 and stayed there. There are constant crashes and rollbacks happening when co-playing, especially when using signs, name tags and spawn eggs. Hard to provide screenshots of the general gitches as it's runtime error (lag mostly with added bonus rollback randomly) [Pictures are screen shots of the worst issue so far]