[Broken Website] Khanacademy HTTP 410

[user655362020]

Checklist

• I'm reporting a broken site support
• I've verified that I'm running youtube-dl version 2020.09.20
• I've checked that all provided URLs are alive and playable in a browser
• I've checked that all URLs and arguments with special characters are properly quoted or escaped
• I've searched the bugtracker for similar issues including closed ones

Verbose log

[debug] Encodings: locale cp1252, fs mbcs, out cp437, pref cp1252
[debug] youtube-dl version 2020.09.20
[debug] Python version 3.4.4 (CPython) - Windows-10-10.0.18362
[debug] exe versions: ffmpeg 4.2.3
[debug] Proxy map: {}
[KhanAcademy] human-anatomy-and-physiology: Downloading topic info
ERROR: Unable to download JSON metadata: HTTP Error 410: Gone (caused by HTTPError()); please report this issue on https://yt-dl.org/bug . Make sure you are using the latest version; type  youtube-dl -U  to update. Be sure to call youtube-dl with the --verbose flag and include its complete output.
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\ytdl-org\tmpksi3o1r1\build\youtube_dl\extractor\common.py", line 632, in _request_webpage
  File "C:\Users\dst\AppData\Roaming\Build archive\youtube-dl\ytdl-org\tmpksi3o1r1\build\youtube_dl\YoutubeDL.py", line 2238, in urlopen
  File "C:\Python\Python34\lib\urllib\request.py", line 470, in open
  File "C:\Python\Python34\lib\urllib\request.py", line 580, in http_response
  File "C:\Python\Python34\lib\urllib\request.py", line 508, in error
  File "C:\Python\Python34\lib\urllib\request.py", line 442, in _call_chain
  File "C:\Python\Python34\lib\urllib\request.py", line 588, in http_error_default

Description

Command used :

youtube-dl --verbose --no-continue --no-overwrites --add-metadata --write-description --write-info-json --write-annotations --write-thumbnail --all-subs --embed-subs --sub-format "srt" --write-auto-sub --output "%(playlist)s/%(playlist_index)s - %(title)s.%(ext)s" --merge-output-format "mkv" --format "(bestvideo[vcodec^=av01][height>=4320][fps>30]/bestvideo[vcodec^=vp9.2][height>=4320][fps>30]/bestvideo[vcodec^=vp9][height>=4320][fps>30]/bestvideo[vcodec^=avc1][height>=4320][fps>30]/bestvideo[height>=4320][fps>30]/bestvideo[vcodec^=av01][height>=4320]/bestvideo[vcodec^=vp9.2][height>=4320]/bestvideo[vcodec^=vp9][height>=4320]/bestvideo[vcodec^=avc1][height>=4320]/bestvideo[height>=4320]/bestvideo[vcodec^=av01][height>=2880][fps>30]/bestvideo[vcodec^=vp9.2][height>=2880][fps>30]/bestvideo[vcodec^=vp9][height>=2880][fps>30]/bestvideo[vcodec^=avc1][height>=2880][fps>30]/bestvideo[height>=2880][fps>30]/bestvideo[vcodec^=av01][height>=2880]/bestvideo[vcodec^=vp9.2][height>=2880]/bestvideo[vcodec^=vp9][height>=2880]/bestvideo[vcodec^=avc1][height>=2880]/bestvideo[height>=2880]/bestvideo[vcodec^=av01][height>=2160][fps>30]/bestvideo[vcodec^=vp9.2][height>=2160][fps>30]/bestvideo[vcodec^=vp9][height>=2160][fps>30]/bestvideo[vcodec^=avc1][height>=2160][fps>30]/bestvideo[height>=2160][fps>30]/bestvideo[vcodec^=av01][height>=2160]/bestvideo[vcodec^=vp9.2][height>=2160]/bestvideo[vcodec^=vp9][height>=2160]/bestvideo[vcodec^=avc1][height>=2160]/bestvideo[height>=2160]/bestvideo[vcodec^=av01][height>=1440][fps>30]/bestvideo[vcodec^=vp9.2][height>=1440][fps>30]/bestvideo[vcodec^=vp9][height>=1440][fps>30]/bestvideo[vcodec^=avc1][height>=1440][fps>30]/bestvideo[height>=1440][fps>30]/bestvideo[vcodec^=av01][height>=1440]/bestvideo[vcodec^=vp9.2][height>=1440]/bestvideo[vcodec^=vp9][height>=1440]/bestvideo[vcodec^=avc1][height>=1440]/bestvideo[height>=1440]/bestvideo[vcodec^=av01][height>=1080][fps>30]/bestvideo[vcodec^=vp9.2][height>=1080][fps>30]/bestvideo[vcodec^=vp9][height>=1080][fps>30]/bestvideo[vcodec^=avc1][height>=1080][fps>30]/bestvideo[height>=1080][fps>30]/bestvideo[vcodec^=av01][height>=1080]/bestvideo[vcodec^=vp9.2][height>=1080]/bestvideo[vcodec^=vp9][height>=1080]/bestvideo[vcodec^=avc1][height>=1080]/bestvideo[height>=1080]/bestvideo[vcodec^=av01][height>=720][fps>30]/bestvideo[vcodec^=vp9.2][height>=720][fps>30]/bestvideo[vcodec^=vp9][height>=720][fps>30]/bestvideo[vcodec^=avc1][height>=720][fps>30]/bestvideo[height>=720][fps>30]/bestvideo[vcodec^=av01][height>=720]/bestvideo[vcodec^=vp9.2][height>=720]/bestvideo[vcodec^=vp9][height>=720]/bestvideo[vcodec^=avc1][height>=720]/bestvideo[height>=720]/bestvideo[vcodec^=av01][height>=480][fps>30]/bestvideo[vcodec^=vp9.2][height>=480][fps>30]/bestvideo[vcodec^=vp9][height>=480][fps>30]/bestvideo[vcodec^=avc1][height>=480][fps>30]/bestvideo[height>=480][fps>30]/bestvideo[vcodec^=av01][height>=480]/bestvideo[vcodec^=vp9.2][height>=480]/bestvideo[vcodec^=vp9][height>=480]/bestvideo[vcodec^=avc1][height>=480]/bestvideo[height>=480]/bestvideo[vcodec^=av01][height>=360][fps>30]/bestvideo[vcodec^=vp9.2][height>=360][fps>30]/bestvideo[vcodec^=vp9][height>=360][fps>30]/bestvideo[vcodec^=avc1][height>=360][fps>30]/bestvideo[height>=360][fps>30]/bestvideo[vcodec^=av01][height>=360]/bestvideo[vcodec^=vp9.2][height>=360]/bestvideo[vcodec^=vp9][height>=360]/bestvideo[vcodec^=avc1][height>=360]/bestvideo[height>=360]/bestvideo[vcodec^=av01][height>=240][fps>30]/bestvideo[vcodec^=vp9.2][height>=240][fps>30]/bestvideo[vcodec^=vp9][height>=240][fps>30]/bestvideo[vcodec^=avc1][height>=240][fps>30]/bestvideo[height>=240][fps>30]/bestvideo[vcodec^=av01][height>=240]/bestvideo[vcodec^=vp9.2][height>=240]/bestvideo[vcodec^=vp9][height>=240]/bestvideo[vcodec^=avc1][height>=240]/bestvideo[height>=240]/bestvideo[vcodec^=av01][height>=144][fps>30]/bestvideo[vcodec^=vp9.2][height>=144][fps>30]/bestvideo[vcodec^=vp9][height>=144][fps>30]/bestvideo[vcodec^=avc1][height>=144][fps>30]/bestvideo[height>=144][fps>30]/bestvideo[vcodec^=av01][height>=144]/bestvideo[vcodec^=vp9.2][height>=144]/bestvideo[vcodec^=vp9][height>=144]/bestvideo[vcodec^=avc1][height>=144]/bestvideo[height>=144]/bestvideo)+(bestaudio[acodec^=opus]/bestaudio)/best" --retries infinite --force-ipv4 https://www.khanacademy.org/science/health-and-medicine

Khan Academy website writes :

This course has been retired
This course is no longer being maintained or updated while we focus our limited resources on other courses.

But I get the same error with other courses that have not been retired.