Suppose that you have a hierarchy that was opened. Do you want to store all the hierarchy breadcrumbs in case you hit refresh, and reload all of them?
Furthermore, what about URLs to initiate an action from a particular context? If you refresh what should it show? It should show a dialog / lightbox above the page, showing the form / interface for filling out before taking this action.
Here is a question for you: what happens when you have a url for a New Issue in github? By itself. It renders a form for a new issue full-page. But now what if I want it as an overlay over a hierarchical state that U navigated to? I should have a longer URL and it wouldnt be full screen anymore.
The main route of the url (example.com/page/subpage) represents the background page of the overlay.
You have two options. 1. Using further subroutes to represent the stage of the overlay if your framework supports it (Ember does) (example.com/page/subpage/form/step1). 2. Using query parans to store the state of the overlay (without the actual data of course): … subpage?overlay=form&step=1
Also breadcrumbs should always mirror the routes. Frameworks, libraries can automatically do it for you.