I really enjoyed Enhancer for YouTube! I initially installed it because it had so many reviews, and have been happy with it every moment since!
The improved page layout and the continued playback screen when scrolling through the page are my top features. But, Enhancer has many more features that I have barely cracked. Lots more to explore!
And have I mentioned it is free?

This addon is pure gold if you watch youtube videos daily. It is subtile but still impressively powerful. One of the most amazing addons i've come across so far!

Great extension! Definitely a must for all YouTube users. Every feature is customiseable and easily fitted to your needs. Big shout-out for the developers

Super je recommande !!! Il y a énormément d'options !

a must-have for youtube users and viewers.

Does a good job, easy to use

Made my life easier!! It's a must have for frequent Youtube users!!! Gives many options! Love it!!

Einfach, unauffällig und sinnvoll - gerade wenn man bei laufendem Video noch andere Dinge zu tun hat (Mail schreiben etc)

comoda e non invasiva

I've used a couple different youtube addons in the past on firefox and chrome. This one has been the best with feature set and quality so far. It does all the things that I've wanted.

Thanx for this tool

Excellent

This extension works great , I especially like the volume control from the mouse, and the other features to change the format ,size etc.

Najlepsi addon pre Youtube

Superb