Pinned Pages for Fast Navigating

When working on a fairly complex website, usually users (for example myself) will create many pages. Currently pages are sorted in alphabetical order, it would be very good and efficient if, for example, users could pin several pages so they would always be at the top to make navigation easier or open pages that are often opened/worked on. It can be a tab (before the themes tab) or a pin on the pages tab that keeps the selected page at the top.

It would be even better if not only the page had this kind of pin function, but also CSS and JS.