How To Reproduce -
Place a hopper on the ground
Fill all five slots with at least one of item A (eg stone)
Throw item B (eg dirt) into the top of the hopper. The hopper will not accept it, as it is full
Throw item A into the top and it will not be accepted until item B despawns
Duplicate of MC-8578, please use the search function to see if your bug has already been submitted. Currently over 54% of tickets are being closed as duplicate.