In a hopper chain items will flow through the chain and clog up in every other hopper all the way down the line and the hopper that is clogged up with gather all items going through the chain and then funnel them out. This makes hopper chains very slow.
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If I understand correctly, what you are seeing has already been reported as MCPE-13417.
If I understand correctly, what you are seeing has already been reported as MCPE-13417.