If a mob is standing in grass, it becomes completely blind. I'm being chased by a zombie, it walks into grass, and it all of a sudden just... freezes.
Linked issues
relates to 1
Comments 3
Cannot confirm for 1.9.2
Is it night or day, is the Zombie standing in tall grass or grass, if it is tall grass does it happen with any double plant?
Possibly a Works As Intended.