A redundant "unable to connect to world" appears if you fail to connect to a recently closed Multiplayer-enabled local world.

How to reproduce

1. Get a friend to open a world with the Multiplayer toggle enabled (if you don't happen to have friends, use an alternate account + device)
2. Make sure you can see that world in the Friends tab
3. Get your friend to leave the world
4. Attempt to join the world when the "Done!" message appears on their side but before the world disappears on your side
   → "Unable to connect to world. The world is no longer available to join." and "Unable to connect to world." both appear separately on the disconnect screen

"Unable to connect to world" should only appear once, either in the top message (thus having only one line onscreen) or the bottom message. This redundancy is somewhat weird, but is of relatively low impact.