I tried both wired directly together and through a router with no internet connection and both prompt the "authentication servers are down" message.
Comments 4
Here is the same issue in 1.8 was not marked as invalid. https://bugs.mojang.com/plugins/servlet/mobile#issue/MC-71386
The reason you cannot play a LAN world offline is that LAN needs basic connection (People within the network need to be able to connect to one another), and the game needs to know who you are.
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However, your ticket has been resolved as invalid.
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