This is no longer maintained, there is a better tool, called LibRedirect that is also open source and much better.
This is a simple and lightweight extension that automatically redirects you from YouTube video webpages to Invidious URLS of the same video. However, it won't redirect you if you are on other YouTube pages.
This is mainly for people who are tired of YouTube ads and don't use Adblockers, OR, people who use adblockers but got blocked in YouTube because of the new "Adblockers are not allowed in YouTube" popup.
Invidious is a free Open Source YouTube client that has no ads. The extension have been tested in the latest version of Microsoft Edge in Linux. You can also select which hosted instance of Individious you want to use.