Note: this fork goes against Dreadrith's, the Original Author, wishes. It is however compliant with the original OS license.
Controller Editor's "Cleanup unused sub-assets" in a standalone and faster script.
Sub-assets are assets embedded into a parent asset but are hidden by default. Certain actions may cause sub-assets to remain as residue in a controller and build up over time without being used and only serve to bloat the controller even further and sometimes even cause issues.
This tool can scan and clean up the residue in your controllers.