When neather mobs agroed, player is attacked by invisable mob entities that result in player damage and death if the player cannot escape via scaffolding, twisting vines, or other mob proof transits. If the game is saved, and re-opened the invisable mobs will be visable (inside closed rooms that should be mob proof, but somehow are breached by the agroed mob entities)
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We're tracking this issue in MCPE-71243, so this ticket is being resolved and linked as a duplicate.
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