Good evening,

Excuse me for my poor english.

I experienced an issue with the activation of vertical pistons.

The first screen shows us the configuration: 2 piston taking alimentation from stone block near them, and redstone torch to tell us if the stone is alimented.

The second screen shows us what happens if we alimente the bottom piston only.

The third screen shows us what happens if we alimente the top piston only.

At the fourth screen we alimente both pistons, every thing works well.

At the fifth screen, we cancel the bottom piston's alimentation: here's the problem.
The bottom piston is still activated while the bottom redstone torch shows that the stone is not powered: the piston should be deactivated.

The screen six just shows us that the redstone torchs don't change anything.

The screen seven shows that system come back to normal if we take away the power.

And the last screen shows the system from his back.

I had this bug on online server and offline on private world on the last version, and both creative and survival.
This is really sad, because we can't deal with the powering of vertical stack of pistons.

exemple of application: double vertical piston system

Thanks for reading me, the redstone mechanics is one part of minecraft that I really love.

I wish you a good week.