We have had 2 farms of chickens fully enclosed, they had been given seeds to produce more chickens. after a few minecraft days they are all gone. we re found chickens and did this process again and once more they are all gone. Cow farm seems to be fine but chickens don't seem to be working as they should. We are testing now with name tags and leads next.
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We're tracking this issue in MCPE-21416, so this ticket is being resolved and linked as a duplicate.
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