Slime block/observer block

Since a few updates, I try all the elevators composed of slime blocks and observers, but the observers do not detect each time, so I used slime blocks and pistons. But since the last two versions where I want to propel myself thanks to this system if I place myself in the center I glitch through the slime block. these two bugs can be linked to detection calculations, I still find it strange to have them on my Galaxy S10 +, which is not already a small phone!