Link to Crashlog:

https://mclo.gs/4PV19op

MC 1.21, Fabric, Chest Tracker 2.4.7+1.21

Can't reproduce so will have a further look later, but for whatever reason Apache Comons Lang3 3.14.0 seems to not be loading right even though it shows in the libraries at the top.

Related to #168

I saw the #168 but sadly cant turn it off to check.
Opening exiting placed Shulkers is perfectly fine, just the on place scan is crashing the game.

im having the same issue as above.

I'll rejig it to not use that library; annoying because it doesn't 'solve' it but I can't figure out why the method/class isn't loading. Let me know if it crops up again.