OP Item Duplication

OP Duplication glitch. Been using this since last summer, recently started a realm and this glitch ruined it so now I want it gone. Searched other bug reports and couldn't find any on this which seems crazy. Also baffled at how easy this glitch is and how it snuck by the bedrock dev team. Oh well. Easy to recreate. 

1. Get a piston to push a chest
2. Right as the piston is about to be powered, simply pull out the items you wanna duplicate.