I’m always surprised when I watch a video that is 9 minutes old and the sponsors segments get skipped automatically. That extension must be getting quite popular.
Can't recommend it enough. And with this plugin you'll immediately notice if a video is vapid (read: only exists to plug the sponsor.)
How does the extension know if the submissions are valid and not malicious?
Users are able to "downvote" a "skip", and a skip which isn't undone is considered an "upvote".