"Invalid player data" error while joining singleplayer world in snapshot 25w41a

patocrrrack show video evidence so they can fix it

Same happened to me, and I think I figured out what caused it in my case. Were you riding a Nautilus when you last exited that save? I tested that and that’s what caused it for me

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We're tracking this issue in MC-302672, so this ticket is being resolved and linked as a duplicate.

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