If a player logs into their world with a alt. account that account receives the same inventory as the previous account. I discovered this while playing LAN with my family, I noticed my stuff was duped over when I switched to a new account to play on.
Say you have a world that you change accounts on, that newer account has all the previous items. The computer/world keeps track of what items the player has but it doesn't compensate for what account is used.
Thank you for your report!
We're actually already tracking this issue in MC-697, so I resolved and linked this ticket as a duplicate.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.
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