Some articles on the internet are frustratingly not always given a publishing date, so you don't know whether the information you are reading is fairly current or way out of date. This add-on just allows you to access www.archive.org quickly to check when they first crawled or found the webpage you are on. By knowing this you have a likely age for the article itself. Just right click on any webpage and select GetLikelyDateofThisPage to get a panel with the results.
You can also left click and drag any link inside of the panel to your Firefox address bar and drop it in to navigate directly there.
Hope you like this extension. Please review it if you have time.