This bug is terrible. A Zombie can kill villagers like this where the villager is inside a house.
Update: We found a way to kill the stuck character using splash potions. Drowning, fire, hitting...nothing works, but splash potions do work. Once she dies, she respawns normally. Definitely a bug.
Seems to be the basic function of placing blocks on carpet since topsnow is similar to carpet. Here is a screenshot (not sure if this is a bug or game design)
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