Problem: If you select a LAN World in muliplayer and press the Delete button then Minecraft Crashes.
How I found it: So me and my brother played some minecraft together and I had to relog because everything froze exept me, so i was going to relog but thought "What will happend if i delete the LAN world" so i did (or tried) and it crashed.
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Duplicate of MC-12731, please use the search function to see if your bug has already been submitted. Currently over 57% of tickets are being closed as duplicate.