The bug
When you click on a recipe or on the crafting book to close the help again you additionally click at your inventory and might pick up or throw items this way.
How to reproduce (crafting help on the left side)
Reproduction steps for 17w18b+
Use these steps if the crafting help is shown on the left next to your inventory.
Picking up items from crafting grid
Right click a crafting table
Put an item in the slot in the middle of the right column of the crafting grid
Click on left border of the book to close it
→ You picked up the item from the crafting grid
Dropping item
Open your inventory
Open the recipe book
Pick up an item with your cursor
Click on the book to close it again
→ The item you were holding is dropped on the right side of your inventory
Linked issues
is duplicated by 2
relates to 3
Attachments
Comments 3
Still happens in 17w17a when clicking tabs. The tab will be switched and any item in your hand will be dropped.
Still happens in 1.12 pre-2 when clicking to open the recipe book while holding an item. The inventory shift can put the item outside the inventory and it will be dropped.
Note that pressing the mouse button down on the recipe book without releasing will shift the inventory, but will not drop the item. The item is dropped on mouse release.
migrated
Please do not mark unreleased versions as affected.
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