When you chain pistons together in a diagonal line using slime/honey blocks the pistons recognize a push limit even though they should all extend at the same time causing no need for one.
MC-165901
Pistons count other pistons connected by slime/honey blocks to the push limit when powered at the same time, but do not try to push them
Open
5
Likely happens because pistons cannot and will not try to push extended pistons or pistons that are in the process of extending or retracting. Before they schedule their block event, they already check whether they can extend, though, and since they can push retracted pistons, they will think they won't be able to push.