I've lost two horses that I had tied up to a fence post and lost them, one after the other. Odd thing was it showed the lead tied to the fence post both times, but would also de-spawn when interacted with. I've also lost several different colored sheep on several occasions along with Librarian villagers in my trading depot.
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Thank you for your report!
We're tracking this issue in MCPE-21416, so this ticket is being resolved and linked as a duplicate.
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