The clients delay applying the received remote state of an inventory they just put an item inside, because otherwise the inventory may revert to an old state if items are moved in rapid succession. I think the problem was that the delay was not applied to the inventory the item is _taken from_, so it was possible that the clients applied an old delayed state even though an item had just been moved out of the inventory. Another problem was that the server didn't create an event for the inventory the item was removed from, so if there were any wrong items in a client-side inventory, they would just be dropped instead of being moved back to the correct inventory.
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