java.lang.OutOfMemoryError: unable to create new native thread

Put the summary of the bug you're having here

*What I expected to happen was...:*for multiplayer to work
Describe what you thought should happen here

*What actually happened was...:*it crashed
Describe what happened here

Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...Find out how to fix the problem
3. ...