Absolutely garbage. Poorly built, tries to charge you money for basic features, puts an annoying button under your videos which directs you to the premium version, and reminds you to purchase it at every opportunity. There is another extension, "Tweaks for YouTube", which provides everything this extension does and much MUCH more, without charging you a penny. In comparison, it makes this extension look like a middle school project.
YouTube Ad Skipper is a browser extension that automates skipping ads on YouTube after the skip ad button is available
It allows for configurations per channel and provides the ability to stop the countdown to skip an ad
The extension also offers features such as setting the duration to play an ad before skipping and muting ads automatically
Users can support the extension with a small annual fee to unlock additional features