When i place a door on glass it breaks and duplicates

Put the summary of the bug you're having here
well i discovered when you place a single door on glass it does not place like normal it instead duplicates into two floating doors on the ground...

What I expected to happen was...:
Describe what you thought should happen here
I thought that it would not let me place it on glass like normal. i originaly tried this to see if in the pocket edition you can place doors on anything but my expectations were two high

What actually happened was...:
Describe what happened here
well i placed it expecting it not letting me place it on the glass but instead when i tried placing it, it did not place but it duplicated into two floating objects instead of one on the ground
Steps to Reproduce:
i dont know anything much about java so i dont know how to get rid of it im sorry my appoligies...
1. Put a step by step guide on how to trigger the bug here
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