Hopper with container above, eg. chest, furnace, etc. is able to collect dropped items.
Steps to reproduce:
Place a chest on a hopper
Add a water-stream at the level of the chest to direct items towards the chest
When items are dropped into the water-stream, they will be collected by the hopper as they are pushed near the chest's hitbox.
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Expected result
A hopper with container above should not collect, or detect, dropped items. From the wiki,
A hopper with a container above it, such as a furnace, chest, or another hopper, cannot collect dropped items; for run-time efficiency, the hopper's code doesn't check for floating items.
Actual result
The hopper is able to collect items due to items entering the smaller hitbox of the chest.
This bug can negatively affect item sorters, item pipes, etc., that rely on "capping" a hopper with a container to prevent dropped items from going where they're not supposed to.
Linked issues
discovered while testing
relates to
Attachments
Comments

This issue was discovered while investigating MCPE-68912. It appears to be a direct consequence of the fix for MCPE-54244. It appears that since hoppers and hopper-minecarts no longer stop searching for inventories and items at the first hopper/chest-minecart they find, they also no longer stop searching for inventories and items when they find a block with inventory to pull from.
This new logic in conjunction with the ability of hopper-minecarts to pull from hopper/chest-minecarts 2 blocks above (see MCPE-57637) allows for pulling to bypass blocks with inventory, including hoppers, in a column. Here are examples:
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