Repository: youtube-dl
Issue: Only some videos can be downloaded from Lecturio
Labels: account-needed

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## Checklist

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Carefully read and work through this check list in order to prevent the most common mistakes and misuse of youtube-dl:
- First of, make sure you are using the latest version of youtube-dl. Run `youtube-dl --version` and ensure your version is 2021.01.03. If it's not, see https://yt-dl.org/update on how to update. Issues with outdated version will be REJECTED.
- Make sure that all provided video/audio/playlist URLs (if any) are alive and playable in a browser.
- Make sure that all URLs and arguments with special characters are properly quoted or escaped as explained in http://yt-dl.org/escape.
- Search the bugtracker for similar issues: http://yt-dl.org/search-issues. DO NOT post duplicates.
- Finally, put x into all relevant boxes (like this [x])
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- [x] I'm reporting a broken site support
- [x] I've verified that I'm running youtube-dl version **2021.01.03**
- [x] I've checked that all provided URLs are alive and playable in a browser
- [x] I've checked that all URLs and arguments with special characters are properly quoted or escaped
- [x] I've searched the bugtracker for similar issues including closed ones


## Verbose log

<!--
Provide the complete verbose output of youtube-dl that clearly demonstrates the problem.
Add the `-v` flag to your command line you run youtube-dl with (`youtube-dl -v <your command line>`), copy the WHOLE output and insert it below. It should look similar to this:
 [debug] System config: []
 [debug] User config: []
 [debug] Command-line args: [u'-v', u'http://www.youtube.com/watch?v=BaW_jenozKcj']
 [debug] Encodings: locale cp1251, fs mbcs, out cp866, pref cp1251
 [debug] youtube-dl version 2021.01.03
 [debug] Python version 2.7.11 - Windows-2003Server-5.2.3790-SP2
 [debug] exe versions: ffmpeg N-75573-g1d0487f, ffprobe N-75573-g1d0487f, rtmpdump 2.4
 [debug] Proxy map: {}
 <more lines>
-->

```
youtube-dl -v --cookies cookies.txt https://app.lecturio.com/#/lecture/c/8466/8468/29284
[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: [u'-v', u'--cookies', u'cookies.txt', u'https://app.lecturio.com/#/lecture/c/8466/8468/29284']
[debug] Encodings: locale UTF-8, fs UTF-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2021.01.03
[debug] Python version 2.7.18 (CPython) - Linux-4.4.0-19041-Microsoft-x86_64-with-Ubuntu-20.04-focal
[debug] exe versions: ffmpeg 4.2.4, ffprobe 4.2.4, rtmpdump 2.4
[debug] Proxy map: {}
[Lecturio] 8468: Downloading JSON metadata
ERROR: An extractor error has occurred. (caused by KeyError(u'content',)); 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.
Traceback (most recent call last):
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/common.py", line 532, in extract
    ie_result = self._real_extract(url)
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/lecturio.py", line 122, in _real_extract
    for format_ in video['content']['media']:
KeyError: u'content'
Traceback (most recent call last):
  File "/usr/local/bin/youtube-dl/youtube_dl/YoutubeDL.py", line 803, in wrapper
    return func(self, *args, **kwargs)
  File "/usr/local/bin/youtube-dl/youtube_dl/YoutubeDL.py", line 824, in __extract_info
    ie_result = ie.extract(url)
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/common.py", line 545, in extract
    raise ExtractorError('An extractor error has occurred.', cause=e)
ExtractorError: An extractor error has occurred. (caused by KeyError(u'content',)); 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.
```
 

## Description

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Some videos from this platform can be downloaded, but the vast majority cannot, I tried to download this and other videos and I always got this problem.

I attach video with a video that I can download and another that I cannot download

https://user-images.githubusercontent.com/58005697/103598392-19e81d00-4ec8-11eb-83b0-dc8b1a18979e.mp4