WebCenter Sites 12c: Contributor Editor Content Tree; having mixed assets under a Tree tab

In the Content Tree area of the WebCenter Sites Contributor Editor, Is it possible to create a Tree tab that has a hierarchy of mixed asset types?

Folder

     -SubFolder

         -Media Asset 1

         -Link Asset 1

         -Content Asset 3

     -SubFolder 2

         -Content Asset 1

         -Media Asset 2

Or, is a Tree tab always organized according to the type of Flex Asset?

In this example, each "Content Folder" is just a parent asset of a "Content" Flex Asset, and, each "Media Folder" is just a parent asset of a "Media" Flex Asset:

Content Folder (Level 1 Parent of Content Asset)

     -Content SubFolder A (Level 2 Parent of Content Asset)

          -Content Asset 1