Is your feature request related to a problem? Please describe.
D8 ships with https://www.drupal.org/project/big_pipe in core:
Describe the solution you'd like
I happened to come across https://github.com/turbolinks/turbolinks, which is a ~37kb js library that seems to be doing a similar thing.
Describe alternatives you've considered
RefreshLess makes navigating your web site faster by only loading the parts that change between pages. Uses the ideas behind Turbolinks technique (pioneered by Rails). But it goes further: thanks to Drupal 8's architecture, we're able to automatically figure out which parts of a page change. So, we only need to send the parts of the page that actually change.
When clicking a link that points to a URL within the Drupal site, we then keep the current page, but just swap the parts that change between the current page and the next. This means less data on the wire, and — most importantly — less work for the browser.