Observers do not send a pulse to redstone when there is a sugar can next to it. It does not send the signal visually either.
Comments 2
Cleaning up old tickets: This ticket had been set to 'Awaiting Response', but has not received a response from the reporter (~3 months+) so is being closed as Cannot Reproduce. If you feel this is still a valid issue then please comment, or create a new ticket following the Issue Guidelines which includes steps to reproduce the problem.
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Can't reproduce in 1.14, is this still an issue for you?