It simply works, and provides a handy and nicely visible download button. To all those not happy with at times missing options for 720p and better downloads, it really is a Youtube evolution problem that forces all developers to keep up all the time. Another extension I had recently totally screwed all page-loads on Firefox for me, so this extension is great, because I never had a crash problem with it. Kudos for a functional option, that is about as good as you can get it. I am especially happy that it works on Linux, because I learned to hate paying M&S or that damned overpriced fruit company for their junk software after working for their tech support in complete frustration for 10 years! So throw the guy a bone and help out, because nothing in life is free, but it is up to you to decide how much you want to give :)