I have been using Easy Youtube Video Downloader Express for the last several years. I download a lot of videos and this is my favorite, and fastest add-on for this job. The download button is currently not showing, due ONLY to YouTube having changed the code on their pages. This has happened several times this past couple of years, and each time, the developer has quickly responded with an update. The developer has already submitted a fix, for this latest YouTube "update", as he did on prior occasions, and it is awaiting approval. Those submitting negative reviews in recent days did so without knowing all the facts. This addon works very well. Please wait for the update.