Whenever I exit my game and reopen it, at least one of the leads in use will be broken, unleashing the entity that was leashed and dropping the lead on the ground (interestingly, however, the fence still shows and acts like a lead is attached, a "ghost lead" if you will).
The same issue happens if I leave the chunk and reenter (e.g., going to the Nether and returning).
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Thank you for your report!
We're tracking this issue in MCPE-157182, so this ticket is being resolved and linked as a duplicate.
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