The animals I capture and put into a fenced in area (smaller than 20x20), they still despawn anyway. I don't even have to log out for it to happen. Randomly they will disappear and its very frustrating when I am trying to create a farm. If there is something that can be done to help my world, and possibly others, that would be awesome.
This issue has already been reported. Duplicate MCPE-21416.
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