When items are deposited into a Dispenser, Dropper, Furnace or Hopper manually or by
Hopper(s)/Minecart Hopper(s), if a Comparator output is attempted to be taken, it will not update automatically. This however does not affect chests or locked chests as shown below. I experimented this bug by placing one item into inventory blocks and attempting to withdraw a comparator output.
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However, this issue is a Duplicate of MC-122159.
It has been linked to this report. If you have additional information, please add it to that report.
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