How to Collect Ground Items Directly Into a Shulker Box
Equipping the Shulker Box
When your inventory is completely full, picking up additional dropped items normally requires placing down a shulker box, moving items inside to free up slots, collecting the drops, and then breaking the box again. You can skip this process entirely by holding a shulker box in your hands.
1. Open your player inventory screen.
2. Pick up a shulker box from your inventory.
3. Place the shulker box directly into your offhand slot (the shield slot), or move it to your active hotbar slot.
4. If it is on your hotbar, you can also hold it and press the swap key (default F) to quickly transfer it to your offhand.
Gathering the Drops
With the shulker box held in your hand or offhand, simply walk over the items lying on the ground. The dropped items will bypass your full player inventory and flow directly into the shulker box's internal storage.
Once you have picked up the items you need, you can swap your tool, shield, or weapon back into your active hands. This allows you to rapidly clear loose items off the ground without leaving anything behind to despawn.