Please add support for the onion URL of invidious.

[onionman774]

Checklist

• I'm reporting a new site support request
• I've verified that I'm running youtube-dl version 2019.12.25
• I've checked that all provided URLs are alive and playable in a browser
• I've checked that none of provided URLs violate any copyrights
• I've searched the bugtracker for similar site support requests including closed ones

Example URLs

• Single video: https://www.youtube.com/watch?v=BaW_jenozKc
• Single video: https://youtu.be/BaW_jenozKc
• Playlist: https://www.youtube.com/playlist?list=PL4lCao7KL_QFVb7Iudeipvc2BCavECqzc

Since invidious is a middle man for youtube, everything but the URL is the same as youtube. That URL is "kgg2m7yk5aybusll.onion"

Description

I would like the onion URL for invidious ( kgg2m7yk5aybusll.onion ) to be supported.

[affinityv]

As an alternative, you can simply pass the video ID and use tor socks proxy as follows:
youtube-dl --proxy socks5://127.0.0.1:9050 -v AH_0a5EoVKc

I actually use an alias as follows and run Tor on port 9350 instead of the default port:
alias ytp='~/bin/youtube-dl --proxy socks5://127.0.0.1:9350 -v'

$ ytp AH_0a5EoVKc
[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: [u'--proxy', u'socks5://127.0.0.1:9350', u'-v', u'AH_0a5EoVKc']
[debug] Encodings: locale UTF-8, fs UTF-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2019.12.25
[debug] Python version 2.7.13 (CPython) - Linux-4.19.0-5-amd64-x86_64-with-MX-18.3-Continuum
[debug] exe versions: ffmpeg 3.3.4-1mx17, ffprobe 3.3.4-1mx17, phantomjs 2.1.1
[debug] Proxy map: {u'http': u'socks5://127.0.0.1:9350', u'https': u'socks5://127.0.0.1:9350'}
[youtube] AH_0a5EoVKc: Downloading webpage
[youtube] AH_0a5EoVKc: Downloading video info webpage
[debug] Default format spec: bestvideo+bestaudio/best
WARNING: Requested formats are incompatible for merge and will be merged into mkv.
[debug] Invoking downloader on u'https://r2---sn-5hne6nsy.googlevideo.com/videoplayback?expire=1577299232&ei=wFgDXv6-E8uz-gaQ8aagDA&ip=192.42.116.17&id=o-AHLe9F5JeNASGwS7KFCocXIX-BUn94yAqEeLWR6WCZAf&itag=299&aitags=133%2C134%2C135%2C136%2C137%2C160%2C242%2C243%2C244%2C247%2C248%2C278%2C298%2C299%2C302%2C303&source=youtube&requiressl=yes&mm=31%2C29&mn=sn-5hne6nsy%2Csn-5hnekn7k&ms=au%2Crdu&mv=m&mvi=1&pl=22&initcwndbps=1101250&mime=video%2Fmp4&gir=yes&clen=10663395&dur=91.099&lmt=1577246884778208&mt=1577277518&fvip=2&keepalive=yes&fexp=23842630%2C23860862&c=WEB&txp=6316222&sparams=expire%2Cei%2Cip%2Cid%2Caitags%2Csource%2Crequiressl%2Cmime%2Cgir%2Cclen%2Cdur%2Clmt&sig=ALgxI2wwRQIgXRJgSTR2qXyyknLabGj2rbhUZ736CPNITNdep_RLas4CIQD9Glqu33wGlNwGsdrJ46en7kr4blq2rduR1w8FRzKkkg%3D%3D&lsparams=mm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AHylml4wRQIgX0a6qiiuZy6gIkbueI3LMEPxZ1oosDDxnN3rNEwM2QoCIQClBOgccBpSgXNAGBKXjfMP1NH3G2PE3DTHqzGd-XiA_g%3D%3D&ratebypass=yes'
[download] Destination: Merry Christmas 🎄-AH_0a5EoVKc.f299.mp4
[download] 100% of 10.17MiB in 00:29
[debug] Invoking downloader on u'https://r2---sn-5hne6nsy.googlevideo.com/videoplayback?expire=1577299232&ei=wFgDXv6-E8uz-gaQ8aagDA&ip=192.42.116.17&id=o-AHLe9F5JeNASGwS7KFCocXIX-BUn94yAqEeLWR6WCZAf&itag=251&source=youtube&requiressl=yes&mm=31%2C29&mn=sn-5hne6nsy%2Csn-5hnekn7k&ms=au%2Crdu&mv=m&mvi=1&pl=22&initcwndbps=1101250&mime=audio%2Fwebm&gir=yes&clen=1501798&dur=91.601&lmt=1577246873770461&mt=1577277518&fvip=2&keepalive=yes&fexp=23842630%2C23860862&c=WEB&txp=6311222&sparams=expire%2Cei%2Cip%2Cid%2Citag%2Csource%2Crequiressl%2Cmime%2Cgir%2Cclen%2Cdur%2Clmt&sig=ALgxI2wwRQIgdXqRHd59f3TgRWwq2IOnlifLHIW7jlet4fKZ92lNkdsCIQDlVYLeUJOgWAfqXqM68KP1V-rnEftTsbHmuQjZ41CYdA%3D%3D&lsparams=mm%2Cmn%2Cms%2Cmv%2Cmvi%2Cpl%2Cinitcwndbps&lsig=AHylml4wRQIgX0a6qiiuZy6gIkbueI3LMEPxZ1oosDDxnN3rNEwM2QoCIQClBOgccBpSgXNAGBKXjfMP1NH3G2PE3DTHqzGd-XiA_g%3D%3D&ratebypass=yes'
[download] Destination: Merry Christmas 🎄-AH_0a5EoVKc.f251.webm
[download] 100% of 1.43MiB in 00:05
[ffmpeg] Merging formats into "Merry Christmas 🎄-AH_0a5EoVKc.mkv"
[debug] ffmpeg command line: ffmpeg -y -loglevel 'repeat+info' -i 'file:Merry Christmas 🎄-AH_0a5EoVKc.f299.mp4' -i 'file:Merry Christmas 🎄-AH_0a5EoVKc.f251.webm' -c copy -map '0:v:0' -map '1:a:0' 'file:Merry Christmas 🎄-AH_0a5EoVKc.temp.mkv'
Deleting original file Merry Christmas 🎄-AH_0a5EoVKc.f299.mp4 (pass -k to keep)
Deleting original file Merry Christmas 🎄-AH_0a5EoVKc.f251.webm (pass -k to keep)