When a piston is powered indirectly (weakly powered) by sitting next to, on top of, or below a directly powered (strongly powered) block, it will cause an attached redstone torch to be turned off. The piston is the only redstone component that exhibits this behavior, and does not occur with the other items that a redstone torch can attach to:
Droppers
Dispensers
Redstone lamps
While this can be potentially useful in certain circumstances, the behavior is inconsistent, and is in direct conflict with the intended behavior of powered vs. activated redstone components.
Additionally, the indirectly powered piston will NOT power/activate any other redstone components, including:
Redstone dust
Repeaters
Comparators
Redstone lamps
Pistons
Droppers
Dispensers
Any and all instances of piston(s) above includes sticky pistons. The behavior is identical.
Linked issues
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We're tracking this issue as MCPE-17909, so this ticket is being resolved and linked as a duplicate.
That ticket has already been resolved as Won't Fix, which means this is considered a bug but won't be fixed. The description of that ticket or the comments might explain the rationale. Please do not leave a comment on the linked ticket.
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