Possible Fixes

Yes

Modpack Version

1.14

What happened?

Pack: ATM10, Version: 1.14 (latest at the time)
Play type: Small 8g of Ram, mobile i5 intel CPU 2.5ghz gaming laptop server with nothing running but the server and an app called Parsec.

Anytime someone comes in the server for a minute or more the server will crash after they leave. Leaving a very generic minecraft/java Arraylist error to what appears to have to deal with either entities in chunks or chunkloading.

Tried removing a few mods and switching them out, but I could not even fathom the amount of mods that could modify either one of those.

This will happen for anyone that leaves the server, every time.

Thank you for your time!

Crash Log

https://gist.github.com/gunnarjessee/9c0fed95d10dd16f34b74ecd5e7a7574

Latest.Log

https://gist.github.com/gunnarjessee/2786b58175488a91418219cdbfb4ff70