Auto Load next Post like qz.com
If you want to go a site builder approach, one solution here is Views Infinite Scroll.


  Views infinite scroll allows you to load and display pages of any view
  inline, using AJAX (this has been called infinite scrolling, load
  more, autopaging, endless pages and more). The pager can be triggered
  with the press of a button or automatically as the user scrolls to the
  bottom of the view's content.


The caveat with this approach is you'd need to rely on a Views page configured with an Infinite Scroll pager set with the Automatically Load Content option. In other words, a static URL showing paged full content. That's pretty close to the functionality, but not perfect replication.