How to "disconnect" master page from its base
I have two one-page master pages called Inside and Outside. I decided to make a more sophisticated master for a whole spread, so I made a spread with an Outside page and an Inside page, added some additional master frames, and did "Save as Master" to create a new two-page master called School. So far so good.

However, now I no longer need Inside and Outside, but if I delete them, all the elements that School is inheriting from them disappear. Can I somehow disconnect them, so that School contains everything and is not based on any other master?
