Step to reproduce:
Joining a singleplayer world
open it to LAN
Make a another account join the world
All games crash (Host and player)
The error in the launcher is:
The game crashed: unexpected error
Error: java.lang.NullPointerException: Cannot invoke "hnc.a(ccy, hkn, double, double, double)" because "$$5" is nullEnvironment
Windows 11, Java 21
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We are tracking this issue in MC-301749, so this ticket is being resolved and linked as a duplicate.
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