'''In-Game:''' If you pick up an already existing object while in-game, that picked up object will retain its original formid. And if you later drop it and click on it, you'll continue to see the original formid.
If a new object is created in game, then it will be assigned modindex FF (i.e., 255, i.e. the last 'slot' available). New objects are created if you buy an item from a merchant or pull an item out a container
(that was not originally placed directly in the game world).
===Where to Find FormIds===