The sticky piston is powered when a block of redstone is one block above the sticky piston (1 block gap of air). This bug works in every directon if the block of redstone is above. But if the sticky piston is pointed down and you remove the block of redstone the piston will stay powered.
Tested with a sticky piston and a block of redstone but its the same for a regular piston
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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