Like in title

What I expected to happen was just item being transported to block with storage (chest, dispenser)

What actually happened was item duplicated in storage

Steps to Reproduce:
1. Place Hopper over some storage (storage must be completly empty, item must be stackable)
2. Throw item into hooper (default key Q)
3. Duplicated item in storage
DOESN'T WORK ALWAYS! Chance is about 40-50%