When a block diagonally next to a piston is being powered by redstone (being redstone dust, repeater, comparator or redstone block), block update next to piston causes it to extend and get stuck in that position until the next block update. If you remove blocks from right to left (referencing the screenshot "after block update") so you get the same setup as in picture "after block removal", piston gets stuck without anything powering it.
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violine1101
Thank you for your report!
We're actually already tracking this issue in MC-108, so I resolved and linked this ticket as a duplicate.
However, that ticket has already been resolved. Depending on the resolution, that can mean that it either will be fixed in the next version, or that it is not considered a bug and won't be fixed.
If you haven't already, you might like to make use of the search feature in the future to see if the issue has already been reported.