TikTok download support

[HACKER-3000]

Checklist

• [ x] I'm reporting a feature request
• [ x] I've verified that I'm running youtube-dl version 2020.07.28
• [ x] I've searched the bugtracker for similar feature requests including closed ones

Description

i think tiktok is large engouth to be featured here. extraction is not hard. just search for the tag and download the src="URL Here" url.

[selfisekai]

tiktok is already supported for like over 1,5 a year: https://github.com/ytdl-org/youtube-dl/blob/master/youtube_dl/extractor/tiktok.py

[HACKER-3000]

huh? I gave ytdl a tiktok url and it said this:

$ youtube-dl "https://www.tiktok.com/@jamesfitzpatrick18/video/6755110763435691269"

[generic] 6755110763435691269: Requesting header
WARNING: Falling back on generic information extractor.
[generic] 6755110763435691269: Downloading webpage
[generic] 6755110763435691269: Extracting information
ERROR: Unsupported URL: https://www.tiktok.com/@jamesfitzpatrick18/video/6755110763435691269

[llacb47]

Duplicate and will be closed as such. Learn to search the issue tracker.

[selfisekai]

ok, made some research, this is an issue - tiktok changed their url scheme. still, it's a duplicate of #23264

[HACKER-3000]

thx