I cannot join the server Mineplex and on other up to date servers I cannot join mini-games and/or other lobby's without crashing the game.

Put the summary of the bug you're having here
Crashing when joining server.
What I expected to happen was...:
Describe what you thought should happen here
I thought I would be able to join like I normally do when getting on.
What actually happened was...:
Describe what happened here
Minecraft crashed.
Steps to Reproduce:
1. Put a step by step guide on how to trigger the bug here
2. Load up Minecraft
3. Go to multiplayer
4. Try to join Mineplex