The game crashed whilst unexpected error The game crashed whilst unexpected error Error: java.util.ConcurrentModificationException

 

How I triggered this crash:

I was on a youtuber called IDMC's server. The glass panes and doors weren't rendering properly on the Creative Roleplay server. I left the laptop for a while and came back to find this crash.

Crash report in comments (it exceeded the 20,000 character limit)