Chest Inventory Duplication Donkey/Llama/Mule

This duplication bug duplicates the inventory of a chest that is attached to a Donkey/Llama/Mule this dupe has been in the game since 19w08a and is still in the game today. You can recreate this glitch by following the steps below.

1) Have Player1 open the chest that's attached to a Donkey/Llama/Mule and put an item you want to dupe in the chest.
2) Have Player2 start to ride the Donkey/Llama/Mule and disconnect
3) Player1 Should now take out all the items from the inventory gui that should still be open on their screen
4) Player4 can now login again and the items should have been duplicated

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