The bug

A chain of hoppers will not transfer items consistently if the hoppers below them become unpowered. Often, one hopper will not transfer items but the others will. This was working in 1.10.

How to reproduce

1. Place a line of containers between eight and 15 blocks long:
   
2. Place a hopper above each of these containers feeding into them.
   
3. Place a line of solid blocks one block behind and one block above these hoppers.
   
4. Place a line of hoppers above the first line of hoppers facing into the solid block.
   
5. Place a chain of hoppers above the second chain of hoppers that feeds down the line of hoppers.
   
6. At the end of the chain of hoppers, place a comparator facing away from the hopper facing into a solid block, place a redstone torch on the side of this solid block and a repeater between the redstone torch and the line of redstone.
   
7. Place redstone dust on top of the solid blocks
8. At the start of the hopper chain, place another hopper with a feeder chest on top.
   
9. Place comparators next to the containers facing away from them.
10. Place at least a stack of items into the feeder chest.
    → Some of the comparators are not lit, indicating no item went into them
    

Additional information

EDIT: This bug breaks some industrial furnace designs. The above instructions will produce a common industrial furnace design if built correctly.

It is possible that the powered/unpowered hopper is not transferring items from the chained hopper above it because the chained hopper is actually empty at the time the powered hopper becomes unpowered.

The empty container appears to be seven from the end if the repeater has the default delay of 1. If the repeater has a longer delay, different containers won't receive items. Delay 1: hopper 7; delay 2: hopper 9; delay 3: hopper 11 and hopper 3; delay 4: hopper 13 and hopper 5.