When a trapdoor is opened by hand, redstone comparators, repeaters, dust, and all rails will stay floating, despite the fact that they cannot be placed opened trapdoors

What I expected to happen was...:

The block on top of the trapdoor should pop off as an item, such as torches, levers, pressure plates and buttons

What actually happened was...:

The block on top stays as a block after the trapdoor is opened

Steps to Reproduce:
1. Place trapdoor with the flat side up
2. Place redstone component or rail on top of trapdoor
3. Open trapdoor manually