There are plenty of plugins, extensions and neat code tricks to download YouTube videos, but none so simple and elegant as Peggo. Newbie users will find the UI simple to use, choose video or audio, length or fragment of file and download. A handy tool for everybody's toolbox.
I remember hunting the internet for something like this a few years ago. There are so many extensions/tools as @andrewpyott mentioned but most are very poorly made. This is super slick.
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