When an item is dropped on a hopper, lets say a redstone torch, it will suck it to a chest there is below, if you drop that redstone torch again on the hopper it will duplicate or even copy itself several times.
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Please do not mark issues as private, unless your bug report is a security issue containing information that may compromise your server/client.
67th duplicate of MC-5998, please use the search function to see if your bug has already been submitted. Currently over 40% of tickets are being closed as duplicate.
Again: Please do not mark issues as private, unless your bug report is a security issue containing information that may compromise your server/client.
Please do not mark unreleased versions as affected. You do not have access to this yet.