Minecraft/Forge version: 1.16.5/36.1.0

Mod version: 2.4.4-forge

Problem: Mobs that are taller than one block consider a one block high tunnel with rails as passable unless the WalkNodeProcessor mixin is disabled.

Consider the example setup in the attached images. Without rails, placing a job block (e.g. a lectern) on either of the yellow concrete blocks reliable causes the villager on that side to claim it. However, when rails are placed either on the blue concrete or on all the green concrete, the villager on the other side might randomly decide to claim the job block instead, pressing into the side where the rails are in an attempt to reach the job block.