I am using the modpack Allusiveness. also known as minecraft but prettier.
In a LAN world with friends, or in single player i can pick up spawners. I change my perspective while carrying a spawner it will crash the game.
Sometimes the crash i will load up, still holding the spawner and unable to crash by changing perspective.

https://pastebin.com/ZuQeFFTX
Version 1.8.0

if its related, my friends will also crash when i pick up a spawner. I will pick it up , be able to change perspective just fine. but the moment i pick it up they crash (sometimes).
They dont get crash reports.

If this crash is a conflict due to another mod, can you please let me know and i will redirect a bug report to them.