According to Google, “Back-forward cache is a browser feature which improves the user experience by keeping a page alive after the user navigates away from it and reuses it for session history navigation (browser back/forward buttons, history.back(), etc) to make the navigation instant. The pages in the cache are frozen and do not run any javascript.”
The good news is that if you use Chrome on desktop, it seems that Google has brought the feature over to the desktop version of Chrome which means that it should be available on Windows, macOS, and Linux. It should be noted that some elements of the website still need to be reloaded, but for the most part it should reload more or less instantly.
It’s a pretty cool feature to have so if you’d like to check it out, make sure that you’re running the latest version and you should be set.