It was half open and half closed. I opened it and same thing.

Steps to Reproduce:

1. Create a door that is one block away from a door(Pressing on the pressure plate shouldn't open the door). 
2. Flatten the pressure plate 3 or so times.
3.  Wait a few seconds then open the door with a wooden axe

Side note: It's easier to trigger the bug is you act like you are confused about the pressure plate not opening the door.