Running Airplane-Purpur version git-Airplane-"6f3677e" (MC: 1.16.5) (Implementing API version 1.16.5-R0.1-SNAPSHOT)
https://nekobin.com/tupucaxeto

Wacky, wonder what weird implementation they're using - we specifically use an iterator there to avoid that very problem.

To be fair that error is really rare and i've never seen it before. So it's not like it's spamming the console.

It should only occur when someone who doesn't have permission for cross-world viewing has an inventory open and gets booted from it. Simple enough fix and it makes the code cleaner, so a good thing to address all around. 👍