Non-stackable item left right click glitch

The bug

If you give yourself two stacks of non-stackable items by using /summon item (for example, diamond chestplate) and then hover over one of the stack and click left the player will be left over holding 127 diamond chestplates. You cannot place them anywhere.

Command: /summon minecraft:item ~ ~ ~ {Item:{id:"diamond_chestplate",Count:64}}