I was trying to make a two way flying machine elevator, as shown in figure 1. However, as shown in figure 2, there are two observers and a sticky piston which have mysteriously appeared, or more accurately speaking, "duplicated." This appalled me, naturally, and upon trying to place some birch planks on one of the observers in figure 3, the observer disappeared entirely. Figure 4 shows that the duplicated piston did not interact with redstone. However, it was able to be pushed down by the flying machine I made as shown in figure 5. Upon further tests I found that these duplicated "blocks," if you can even call them that, disappear if moved by pistons/sticky pistons, or are pushed into an actual block by the flying machine. Sometimes they even disappear randomly when pushed downward by the flying machine. I personally think this duplication glitch is similar to "ghost blocks" that are seen on large and laggy servers, but to have this happen on a single player creative world is truly appalling.