It is based on the popular youtube-dl command line tool, but much easier to use, especially with videos/playlists that require a login (like your personal "Watch Later" list).
@emanuele is it open source?
@mandycandy ViDL is not (AFAIK), youtube-dl is. Anyway, you can instal youtube-dl using brew on your system and use it via command line if you prefer.
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