So, there is this bug on multiplayer servers where players can duplicate any single item using a Llama or a Donkey.
Player 1 sits on the Llama and puts the item inside it's inventory then dismounts it. Player 2 then shift-clicks it to access it's inventory. Player 1 then disconnects and the Player 2 takes the item. After that Player 1 comes back and opens the Llamas inventory, the item is still inside and he can take it. Boom, item duplicated. I don't want my server members to do this, so please try and fix it. Thank you.