Love everything about this Extension. It is very feature filled and works amazing. it really has change the experience I have had using YouTube and I Highly recommend this Extension to all YouTube Users.
My only only issue is that I would like to see it update to version 3.x like in Chrome. Firefox has version 2.x and fulfills almost all of my needs but i have become accustomed to the certain new features on version 3.x, such as the ability to adjust the number of videos or shorts that are show in each rows and some of the theming abilities.
The extension is worthy of 5 out of 5 stars but I gave it 4 stars because i would like to see the new version 3.x on Firefox instead of 2.x