Firefox: Usable Home Button transforms the “Home” button in Firefox to a quick button that takes you to the homepage of any website you’re visiting. So for example, if you were reading this article with it installed, one click would take you right back to the Lifehacker main page.
After all, you probably see your actual home page or new tab page every time you open a new tab or window, so you may not use the Home button that much anyway. On some sites, like ours, the main page is just one click away, on the logo at the top or some other “home” link—on other pages though, it can be tricky to get back to the main site (or the domain root) once you’ve been browsing for a while. This add-on makes getting back where you want to be super simple.
UsableHomeButton | Mozilla Add Ons