As the title suggests if a mob walks over a block that is covered by a pressure plate as it wanders or pathfinds it will start to jump as it moves. It happens to every mob that is 1 block wide and walks without jumping already. It does happen on all pressure plates.
Steps to reproduce
Place a ring of 8 pressure plates on top of solid blocks, leaving a center block with no pressure plate on top.
Spawn a zombie in the middle of the ring, on the block without a pressure plate.
Spawn a villager outside of the ring.
Expected result
The zombie walks toward the villager.
Actual result
The zombie jumps when pathing over the pressure plates.
Related issues
is duplicated by
relates to
Comments

Confirmed that mobs jump while pathing over pressure plates. I do not see them jumping continuously (the way they do on buttons, for example) so I have updated the summary accordingly.