Well, basically the chiselled shelf is charging the redstone comparator, even without books. The only way to remove the charge is to break and replace the block, but after 1 book is placed, The bug occurs again. It's old, but it's never been fixed. That's why I'm reporting. Attached is the video of the bug in action. Again: The bug is an invisible load that should not occur on the chiselled shelf, and that prevents dozens of systems.
Thank you for your report!
We're tracking this issue in MCPE-163371, 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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