Confirmed for MC 1.13-pre2.I reproduced the bug with all the types of rails and the zombie does not cross them.I'm pretty sure this is a developing error. The Gamepedia says: "Zombies will attempt to avoid obstacles, including sheer cliffs and lava, and will try to find the shortest path towards the player."However, Zombies can jump blocks and slabs, it's weird they cannot come accros rails.
Confirmed for MC 1.13-pre2.I reproduced the bug with all the types of rails and the zombie does not cross them.I'm pretty sure this is a developing error. The Gamepedia says: "Zombies will attempt to avoid obstacles, including sheer cliffs and lava, and will try to find the shortest path towards the player."However, Zombies can jump blocks and slabs, it's weird they cannot come accros rails.