It would be helpful if each resource allowed a user to create an outline of the resource that displayed in the sidebar (along with the table of contents and notes).
This use outline would function as a quick jump-to guide.
Here is the specific use case that brought this to mind:
Suppose that I'm wanting to quickly find the main section where x is discussed in a resource like the Republic or the Nicomachean Ethics--resources that don't have headings for books or sections. If I was able to create my own outline, I could easily mark a section of the resource where, say, Plato's analogy of the cave occurs in the Republic or courage is discussed in Nicomachean Ethics.
