Leave game dupe bug

as you can see in the video, if you have 65 diamonds, and your inventory is full, one diamond will be on the floor, but if you press E and click on the 64 diamond, the one diamond will be in your inventory, and you just close your inventory, and then that one diamond will be droped on the floor, and if you do this a lot of times, you will only get one stack of diamond, now to leave the game and rejoin, now if you press e you will get another 64 diamonds

Credit-TUJIANG on youtube

My mc user-KIRA_opYT