Monsters are able to path find players and villagers even if they inside a block

When villagers and players are in a block without glass and covered inside a block they somehow are still able to pathfind them like they have x ray vision.

 

How to do:

Go on a creative world

build a windowless house

have a player in there or place a villager in

place a zombie near

the zombie will be able to pathfind the villager or player.