Piston heads occasionally appear twice in certain piston setups

The bug

Occasionally, during the retraction of pistons, the piston head appears twice. This is not consistently an issue, but it still happens once in a while.

How to reproduce

Build a flying machine as shown in the pictures below:

Then, update the observer on the bottom to activate the flying machine.

Notice that on occasion, one of the pistons in the flying machine shows with two piston arms. This is a difficult bug to reproduce; I used a screen recorder to be able to see the double extension (as I can slow down the recording using it).

A screenshot with my F3 debug menu is attached. I can also confirm on my other computer, for which you can see the F3 debug menu on MC-194175.