Pressure Plate (Light)

So I was building a map for Skydoesminecraft when I decided to put Light Pressure Plates as it is gold and you need a stack of items.I expected them to use the other kind of Melons to make the iron door open.

I thought you need a stack of items to open the door...

So I put on a test Drive for it. I accidently stepped on the pressure plate and the doors open.
I didn't even put the melons on the plate

Steps to Reproduce:
1. First get to Creative mode.
2. Put iron doors and light pressure plates to trigger the door.
3. Get to survival mode.
4.Step onto the pressure plate and see what I mean.

This screenshot can show a little proof.