Several LAN worlds on the same network can cause a client crash

On a LAN network with several (tested ~100 for fun) worlds open to the same LAN the multiplayer screen has a chance to crash.

This is due to concurrent modification on the collection that stores the results of the UDP lookups (stacktrace below w/ crash report).

For quicker reproduction of the issue, send ~1000 falsified payloads over the network and you will almost certainly get a client crash.

Only known to occur on the multiplayer screen (for obvious reasons).