At first I gave it 3 stars because it only seemed to work half of the time. Now I am dropping it to 1 star because not only does it still not work most of the time, but it started freezing up Firefox. I only have 12 tabs (plus 7 pinned/app tabs) open and a yellow bar appears on the screen saying "A script in the extension "Back to Close WE" is causing Firefox to slow down." It then gave the options to temporally disable the extension on the current page, stop it, or wait. Instead I chose to remove the add-on entirely. I'm not sure if there is any other way I can accomplish this feature, but its not worth bogging down my entire browser.