Recipe book duplication glitch

Video

https://www.youtube.com/watch?v=M2vWfEUGV0c

FAQ - How this works (read description)

• Crafting and recipes are now handled server side
• This may have some quirky behavior
• The server sees items in your inventory that aren't there
• Server happily continues giving you items

Steps to reproduce

1. Get at least 18-27 of an item you can craft into a block and back (diamonds, redstone, wheat, slime, etc.)
2. Open your recipe book on the page where the block is located (in a crafting table)
3. Spam click on the resulting block (the faster the better)
4. Occasionally, it will grab more items than there are in your inventory, now with more items in the grid, either take them out and repeat the process, or just craft them into block form

How to dupe other things

1. Make sure you can at least make 2 or 3 of the result item with the items you currently have
2. Same as step 2 and 3 above
3. Instead of crafting the result item, just take the items out of the grid and repeat