When some transparent blocks are placed above an opaque block, and you're allowed to interact with the surface of that opaque block (for example, by placing a pressure plate and looking at the borders of the block underneath it), whenever you place redstone dust on that block, the previous transparent block just dissappears.
This also applies when placing transparent blocks that depend on another block behind it (like ladders and torches), placing redstone on the block below will make them dissapear.

Affected blocks:

• Buttons
• Pressure plate
• Torches
• Redstone Torches
• Ladders
• Doors
• Levers
• Tripwire hooks
• Trapdoors
• Glass Pane
• Vines
• Grass (I believe this is inteded, but still might be part of the bug)
• Iron Bars
• Banners

STEPS TO REPRODUCE

• Create a map in creative mode
• Grab any of the above mentioned blocks and redstone dust.
• Place those blocks in the way they're supposed to be placed, but always having a solid block below them
• Face the block below them, and place redstone dust
• The item is replaced by redstone dust, and not even dropped as a resource

The images below are a sequence of screenshots showing the bug with several blocks