ISSUE: Using a sticky piston with a redstone block to activate another sticky piston with a redstone block in a VERTICAL line causes the second piston (lower) to stay activated it's redstone block power source has been removed.
Does not affect Horizontal setup.

DISCOVERED: I was testing an idea for vertical transmission with intent to transfer a signal from a daylight sensor down a tower and across the ground to several lights.

TO REPEAT: Setup a vertical piston line similar to one in the attached image. I used a redstone block to activate the top piston but I also tried it with a lever. I have not tried it with a daylight sensor (I was still toying around with the idea and wasn't sure it would work).

ASIDE: As it stands this glitch may somehow work for a Block Update Detector but it's also not working as a vertical transmission device.

EDIT: Forgot to mention there was another similar bug report I thought may be the same but it wasn't clear: https://mojang.atlassian.net/browse/MC-8328