Tutorials/Block and item duplication – Minecraft Wiki
In a bedrock world, my friend experienced a duplication glitch with shulker boxes in an ender chest. (They don't 100% match up in this clip due to consolidating/ organizing items) : r/Minecraft
Tutorials/Block and item duplication – Minecraft Wiki
Minecraft Xbox One & PS4: [Chest] How to Duplicate Items with a Chest! | Chest Duplication Glitch! - video Dailymotion