[MCPE-19138] Pistons stuck- sometimes don't overwrite the Piston Extension with Air

Occasionally (unable to reproduce reliably) pistons get stuck in the closed position no matter how many times you power and unpower it, and give it block updates.
I have determined the cause: The Piston Extension block (I believe it is ID #36) is the block which is used during the extending/retracting of a piston. After the piston is done moving, the Piston Extension should be overwritten by air or the block being pushed, however sometimes it stays. Because it is unpushable, the piston gets stuck. The piston moves once you break the Piston Extension.
I believe this bug is caused when the game crashes while the piston is moving. This is just my theory. Please fix this, it is causing redstone machines to stop working.

As you can see in the last image, once you break the Piston Extension in front of the piston it opens the piston

Linked issues

is duplicated by

MCPE-22625 Pistons fail to extend

MCPE-22930 Piston bug

relates to

MCPE-17464 Extended pistons retract for a second when the world is loaded.

Attachments

Piston-Extension-Glitch.mcworld

Comments

migrated 2016-12-11T22:15:23Z

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migrated 2017-03-01T13:12:31Z

I can confirm this exists in 1.03.

I have a row of pistons that extend across a chunk boundary. on occasions when the chunk is loaded, pistons in one of chunks will load as previously described. The problem can be cleared by destroying the wooden surface of the piston. The piston will then extend as expected.

so far, it has only happened in one of the chunks and not the other, it is usally all the pistons in the affected chunk that are in this state, but I have seen on one occasion that only some of the pistons are affected.

Running on android 6

migrated 2017-04-06T04:05:14Z

Confirmed on 1.0.5 / iOS.
I will upload a test world later today which can be used to reproduce the problem fairly reliably.

migrated 2017-04-06T11:55:41Z

Attached a test world.

How to reproduce:

Enable the clocked pistons by activating the lever.
Reload the world repeatedly until something strange happens.

Unexpected results:

Piston extensions can stay there as described in the ticket.
Sometimes pistons get broken for apparently no reason, destroying the whole circuit.

My observations:

For whatever reason the chance of the glitch happening increases when pistons are in contact with some liquid.
Spam-clicking the tp button while pistons are clocked sometimes leads the world to crash, which may or may not be relevant to this bug.

migrated 2017-08-27T14:45:28Z

It even happens without the game crashing or exiting the world