What I expected to happen was...:
Connect to server without problems.
What actually happened was...:
Your player is duplicated and you have to wait for your duped player to leave before it is possible to reconnect, or else you get a ReadTimeOut exception
Steps to Reproduce:
1. Connect to Server, then leave
2. Attempt to reconnect
3. Get an error, and you have to wait for the duped players to leave before reconnecting
Seems to only do it in Multiplayer
Linked issues
Comments

Unfixable. MC-37586