In Windows 10's Minecraft Preview, from time to time in old cities the redstone system that opens the door is very buggy. Honestly, I don't know if this is a bug, but it's bizarre the way it appears. I just want to let you know that in the video I left below, I didn't destroy any blocks. I am teleported to an ancient city and found the redstone system that opens the door this way. Please if this is a bug, please fix it.