How to create simple markdown pages within documentation (that are not bound to a request)

For example, here is my documentation page. I understand that you can edit the collection to create a simple markdown document. Any headers you create are automatically created as clickable links on the left, however, how can I also create sections within each collection?

As of now, there is no way to add custom markdown pages.

Looking for the exact same. Sorry to see there is no way to do this. Seems so simple. Give an option to create a page without prefixing the title with GET, POST, etc.