This is my first complaint, just making sure you know if I mess up anything.

I randomly found a problem with trapdoors playing in survival. It seems Mobs think trapdoors do not exist, kind of like doors. I saw this in 2 different things I built.

The first thing was a chicken coop. I used trapdoors as walls for the chicken coop to take up less space, but the chickens treat the trapdoors like doors where they do not walk around and find an opening but just try to run through the trap doors. The reason this might be hard to fix is that I also used the trapdoors as doors as well as walls so they will treat the door like a wall to if you change it. 

The second thing a made that has the same problem is the pig pen. the pigs always horde the walls of the pig pen and constantly jump on the sides to try to get out. they don't treat the trapdoors as walls but as doors so they act like they can just jump through.

If you could please fix this that would be great because this is really annoying and it also makes it hard for me to get the animals back into their shelters because they just try to walk through the giant obstacle.