Preloads help you to change behavior or add functionality to an existing app without having to modify the app code. You can configure preloads for your apps on the Optional screen.
Finsemble provides some preloads for you, and you can also add your own:
Note: This URL for your preload must be valid. Finsemble verifies whether the string you provided is a URL, but it won’t verify for you whether the URL points to actual preload code. It’s on you to verify that the location is correct.
Introduction to Smart Desktop Designer