When using a sticky piston to extend a redstone block, when the piston is extended it does not retract to it's 1 block form when the redstone block is broken or moved away from the piston. This also works with the normal piston.
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Thank you for your report!
We're tracking this issue in MC-108, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as working as intended, which means this is not considered a bug and won't be fixed. Please do not leave a comment on the linked ticket.
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Duplicate of MC-108.