Minecraft wiki entry for Development_versions, associated text: Components
Added a Lock in Inventory (minecraft:lock_in_inventory) component that can be applied to an item via the /give and /replaceitem commands. This prevents the item from being removed from the player's inventory, dropped, or crafted with.
Added a Lock in Slot (minecraft:lock_in_slot) component that can be applied to an item via the /give and /replaceitem commands. This prevents the item from being moved or removed from its slot in the player's inventory, dropped, or crafted with.
Added a Keep on Death (minecraft:keep_on_death) component which can be applied to an item via the /give and /replaceitem commands. This component prevents the item from being dropped when the player dies.