PeacefulCraft uses AntiDrop to help prevent accidental item droppable, especially into farm hoppers.
What is AntiDrop?
AntiDrop is a plugin that will prompt you to confirm dropping an item before actually removing the item from your inventory. The full list of items that are protected is shown below.
  - GOLDEN_PICKAXE
 
  - GOLDEN_SHOVEL
 
  - GOLDEN_SWORD
 
  - GOLDEN_AXE
 
  - IRON_PICKAXE
 
  - IRON_SHOVEL
 
  - IRON_SWORD
 
  - IRON_AXE
 
  - DIAMOND_PICKAXE
 
  - DIAMOND_SHOVEL
 
  - DIAMOND_SWORD
 
  - DIAMOND_AXE
 
  - NETHERITE_PICKAXE
 
  - NETHERITE_SHOVEL
 
  - NETHERITE_AXE
 
  - NETHERITE_SWORD
 
How To Use?
AntiDrop is enabled by default. If you try to drop one of the items on the list, you will be prompted to drop the item a second time as confirmation you actually meant to drop the item.
Commands
/ad enable Enable AntiDrop protection. 
/ad disable Disable AntiDrop protection.