3sat 'unsupported url'

[LinuxOpa]

Checklist

• [ x] I'm reporting a broken site support
• [ x] I've verified that I'm running youtube-dl version 2019.06.21
• [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

[debug] System config: []
[debug] User config: []
[debug] Custom config: []
[debug] Command-line args: [u'https://www.3sat.de/dokumentation/natur/wachau-land-am-strome-100.html', u'-v']
[debug] Encodings: locale UTF-8, fs UTF-8, out None, pref UTF-8
[debug] youtube-dl version 2019.06.21
[debug] Python version 2.7.15+ (CPython) - Linux-5.1.12-050112-generic-x86_64-with-Ubuntu-18.04-bionic
[debug] exe versions: ffmpeg 4.1, ffprobe 4.1, rtmpdump 2.4
[debug] Proxy map: {}
[generic] wachau-land-am-strome-100: Requesting header
WARNING: Falling back on generic information extractor.
[generic] wachau-land-am-strome-100: Downloading webpage
[generic] wachau-land-am-strome-100: Extracting information
ERROR: Unsupported URL: https://www.3sat.de/dokumentation/natur/wachau-land-am-strome-100.html
Traceback (most recent call last):
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/generic.py", line 2340, in _real_extract
    doc = compat_etree_fromstring(webpage.encode('utf-8'))
  File "/usr/local/bin/youtube-dl/youtube_dl/compat.py", line 2551, in compat_etree_fromstring
    doc = _XML(text, parser=etree.XMLParser(target=_TreeBuilder(element_factory=_element_factory)))
  File "/usr/local/bin/youtube-dl/youtube_dl/compat.py", line 2540, in _XML
    parser.feed(text)
  File "/usr/lib/python2.7/xml/etree/ElementTree.py", line 1659, in feed
    self._raiseerror(v)
  File "/usr/lib/python2.7/xml/etree/ElementTree.py", line 1523, in _raiseerror
    raise err
ParseError: not well-formed (invalid token): line 134, column 862
Traceback (most recent call last):
  File "/usr/local/bin/youtube-dl/youtube_dl/YoutubeDL.py", line 796, in extract_info
    ie_result = ie.extract(url)
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/common.py", line 530, in extract
    ie_result = self._real_extract(url)
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/generic.py", line 3316, in _real_extract
    raise UnsupportedError(url)
UnsupportedError: Unsupported URL: https://www.3sat.de/dokumentation/natur/wachau-land-am-strome-100.html```


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