Youtube favorites are like bookmarks for sites in the browser, but only for videos. This extension allows you to work with links to videos, channels, playlists in youtube, as well as you work in your operating system with files - copy, delete, move, create folders.
Now you do not have to look for the video you need in the history or in the "watch later." Open videos in pop-up windows (as many as you want). Also you can create bookmarks for timestamps in a video clip, which will allow you to jump to the right moment in one click.