When placing a piston (sticky or not) facing up with a block on top then powering that block from above with a button ON TOP (putting the button on the side of the block won't create the bug), the piston will push the block up, but the block will be invisible during its movement. This is not a visual bug. If the pushed block is a slime and you stand on it, you will not be launched up since the slime is technically not there. Also, this bug does not occur with levers (as shown in the video), and works slightly differently with pressure plates. This bug is present in all versions/snapshots after 1.18.2.