Minecraft wiki entry for Development_versions, associated text: Trapdoor collision now matches their visual shape. (MCPE-13451)
Paintings can no longer be placed on top of item frames.
Cactus blocks now break when next to lava.
Flowers in snow now break properly and drop the correct item. (MCPE-30147)
Falling blocks no longer break when falling on ice blocks and glass.
Falling blocks are now broken by partial blocks that are placed above piston arms facing up.
Mycelium no longer wrongly turns to dirt due to not having enough light.