Enhancer for YouTube™
This is my preferred extension for YouTube™ because I have added all the features that I personally need to make YouTube™ more awesome. I use it all the time, and since it is also used by almost 100,000 users there are chances that it will improve your watching experience too if you are looking for a lightweight and useful extension for YouTube™.
One of the most appreciated feature is the possibility to remove ads on-demand to permit channels users are subscribed to to earn revenues from those ads so that they can continue to produce great videos—which is not possible with well known ad blockers—but also to remove ads that can't be skippped and that have been already watched.
I have planned to add more features if the extension gets a lot of ★★★★★ so if you like it take a minute to rate it and leave a positive review!
Enhancer for YouTube™ can be installed on Chrome, Firefox, and Opera, and thanks to the help of enthusiast users it has been translated in more than 30 languages! If you don't already use it and want to give it a try, click the button that corresponds to your browser, then click on either the "Add To Chrome" or "Add to Firefox" or "Add to Opera" button.