I don't know if it's a bug or just because of my computer. At least some Redstone techniques no longer work that have to do with observers or pistons. So far I have noticed that the simple elevator with observers, adhering pistons and mucus does not work and when I power a sticky piston with an observer, the piston pulls back the block it has in front of it instead of letting it go. This means that i don't have 3 by 3 doors. I've already tried to reinstall Minecraft or play without a multiplayer account. It didn't work. The techniques in the attached Picture doesn't work either. The Piston doesn't stay with me above.