After the copper golem collects an item from the copper chest that isn't in any nearby chests, it must have dropped it after pressing the Use button, but it doesn't. Tried with an empty hand, with and without secondary item like shield, still doesn't drop.
Thank you for your report!
We're actually already tracking this issue at MCPE-228459, so I will resolve and link this ticket as a duplicate.
I suggest also to browse through the main issue for potential fixes.
If you would like to add a vote and any extra information to the main ticket it would be appreciated.
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