Rated 5 out of 5 stars
A very simple and unobtrusive, yet helpful add-on.
It's so unobtrusive that I installed it, didn't visit Youtube for a few weeks, and forgot about it. Then, when I went to Youtube and did some browsing, I saw the effect of the add-on but thought to myself that it must be a new UI feature of Youtube - it's that elegant and well-made that it completely blends in to the website.
I don't use Youtube too much, but this add-on makes doing so a more pleasant experience.