Currently, clearing your inventory brings up a confirm dialogue so you don’t delete things by accident, but filling your inventory with an item deletes your entire inventory whether you intended for it or not.
When items are spawned in or duplicated, the new items would preferably be placed in the earliest open slot or display an error if there are none (as is done with the catalog to pocket cheat). Spawning in sets of items would only spawn in items if their intended slot was empty.

Places where spawning items deletes existing items occurs:

• Text to item (item to first slot)
• Text to item (item set to inv)
• Text to item (item on floor to inv)
• Duplicate items (duplicate)
• Duplicate items (duplicate all)
• Get inventory set
• Custom inventory button - Duplicate