(its or 1.18 too ) When you put 2 redstone blocks on top of a piston and remove the fisrt one that is on contact with piston you remove. You will see that is  still activated. ok its not a bug. But if you remove  the second redstone block you will see that is STILL activated!! (in 1.18.1 if you place a block or breake under or in sides it will update in not activate)