https://gist.github.com/bogger33/0cd6120420a754baaefec31c614a7660

Using speigers chunk pre-generator to generate chunks on my server, and occasionally recurrent complex will crash.

I'm getting the same issue with my 1.11.2 server

https://gist.github.com/kwpugh/5fd6cf96531bfa5deff147c961a2a7b6

Duplicate of #223.