Multiple Duplication Glitches

There's this glitch where you can duplicate stuff with pistons and chests and it really affects realms due to some players getting tons of diamonds from duplicating, it just makes the game unfair. Would want to fix this glitch in the future.

Theres even a second method of duping by creating an auto dispensing dispenser shooting diamonds into a players inventory, the player opens a crafting table and rapidly clicks on the craft diamond blocks icon. Somehow it duplicates the diamonds in the crafting grid and with enough diamonds in the dispenser, the player will be able to create a stack of diamonds blocks every time. This is also a duplication glitch that needs fixing.