Someone with the Minecraft username Buterfiend keeps crashing me and my friend and I'm upset.

Put the summary of the bug you're having here

What I expected to happen was...: to join a server i liked
Describe what you thought should happen here

What actually happened was..someone crashed me because I didn't answer their call.:
Describe what happened here
He hacked my Minecraft and crashed me.
Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. ...
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