When I am in the comment file (.DXC) for an assembly, there is a page called Introduction and another called Getting Started that I can edit. For the Introduction page and Getting Started page (and even the Assembly overview page), why not have the tabs for seeing the content in these three ways: Normal, HTML, Preview, as you do for the other tagged content such as Summary and Remarks?

Does that make sense? 

Getting Started and Introduction pages are Content Types, just the same as Summary, Remarks etc. Just switch to the required content type (Introduction or Getting Started) and choose between Normal, HTML, Preview.

Oh, I see my mistake. Thanks. Of course, the user interface is logical. I just didn't use it right. I was selecting the page at the top, but I was not selecting the content type further down the list. Now I see it. And once selected, it has the three tabs as I expect. Thanks!