Unlister is a web app that you can use to see if a playlist or a list of YouTube video URLs references a video marked Unlisted, i.e., only visible to users that a link to the video. That way, you can quickly take action on those unlisted videos before YouTube makes them private on July 23, 2021.
Check out a live version of this web app and take action on your favorite unlisted videos here!
Special thanks to Sethycakes for this idea (and requesting it in the first place)! 😊
TODO