Alright, that's a pretty clear answer. Unfortunate but entirely understandable. Thanks for explaining.

Yeah, I was imagining it being put in the player's (or the tank's) inventory and if full, drop it on the floor.

I was playing with the idea of giving the player back steel/a fuel tank item when they consume a full canister of flamethrower ammo and I think that adding an extra optional property for a spent_result to the AmmoItemPrototype would be a cleaner and simpler solution than anything I can come up with ...