Basically when you break the block beneath the door, the door duplicates and drops x2 of itself.

When breaking the block above the newly added doors, it basically duplicate. 

What I expected to happen was...:
What should have happened was it should have dropped itself not two of itself.

What actually happened was...:
It gave me x2 doors instead of just the one that I was supposed to get.

Steps to Reproduce:
1. Break the block underneath the door