[9gag] Adjusted for current website

[DrWursterich]

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The website has changed in the past 4 years and the original extractor stopped working. I rewrote it to be able to handle this.

[woutershep]

Patch still seems to work fine and allowed me to actually download a clip from 9gag.
Without this patch i just get a ERROR: Unsupported URL.
Any reason why this hasn't been merged yet?

[sayem314]

@dstftw

[Mennaruuk]

Hi! Is there any update regarding ability to download 9GAG videos using youtube-dl? Thank you for your help!

[Mennaruuk]

Thank you 🙏