Issue: When someone places a hopper next to a block that is in the powered state the hopper does not visually appear to others. But it does appear to the person who placed it. Any attempt by others to place a block in that location will cause the placed block to vanish and the hopper to appear just like with ghost blocks. When you cant see a hopper and you right click the place where it should be the hopper will appear suddenly.

How to Reproduce: Use a powered block (I used redstone block) and have another person place a hopper so the hopper touches any side of that block. The person placing will see the hopper but others will not be able to.

Conditions: Must be a hopper placed by another person and must be placed on or beside a block in the powered state.