Could not find JS function u'gr'

[main--]

$ youtube-dl --verbose 'https://www.youtube.com/watch?v=ZEf9FxlQRLA'
[debug] System config: []
[debug] User config: []
[debug] Command-line args: [u'--verbose', u'https://www.youtube.com/watch?v=ZEf9FxlQRLA']
[debug] Encodings: locale UTF-8, fs UTF-8, out UTF-8, pref UTF-8
[debug] youtube-dl version 2015.11.27.1
[debug] Python version 2.7.11 - FreeBSD-10.2-RELEASE-p8-amd64-64bit-ELF
[debug] exe versions: ffmpeg 2.8.3, ffprobe 2.8.3, rtmpdump 2.4
[debug] Proxy map: {}
[youtube] ZEf9FxlQRLA: Downloading webpage
[youtube] ZEf9FxlQRLA: Downloading video info webpage
[youtube] ZEf9FxlQRLA: Extracting video information
[youtube] {22} signature length 43.43, html5 player en_US-vflrSqbyh
[youtube] ZEf9FxlQRLA: Downloading player https://s.ytimg.com/yts/jsbin/player-en_US-vflrSqbyh/base.js
ERROR: Signature extraction failed: Traceback (most recent call last):
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 856, in _decrypt_signature
    video_id, player_url, s
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 771, in _extract_signature_function
    res = self._parse_sig_js(code)
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 834, in _parse_sig_js
    initial_function = jsi.extract_function(funcname)
  File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 241, in extract_function
    raise ExtractorError('Could not find JS function %r' % funcname)
ExtractorError: Could not find JS function u'gr'; 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.
 (caused by ExtractorError(u"Could not find JS function u'gr'; 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.",)); 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/youtube.py", line 856, in _decrypt_signature
    video_id, player_url, s
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 771, in _extract_signature_function
    res = self._parse_sig_js(code)
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 834, in _parse_sig_js
    initial_function = jsi.extract_function(funcname)
  File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 241, in extract_function
    raise ExtractorError('Could not find JS function %r' % funcname)
ExtractorError: Could not find JS function u'gr'; 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/YoutubeDL.py", line 663, in extract_info
    ie_result = ie.extract(url)
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/common.py", line 290, in extract
    return self._real_extract(url)
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 1410, in _real_extract
    encrypted_sig, video_id, player_url, age_gate)
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 866, in _decrypt_signature
    'Signature extraction failed: ' + tb, cause=e)
ExtractorError: Signature extraction failed: Traceback (most recent call last):
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 856, in _decrypt_signature
    video_id, player_url, s
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 771, in _extract_signature_function
    res = self._parse_sig_js(code)
  File "/usr/local/bin/youtube-dl/youtube_dl/extractor/youtube.py", line 834, in _parse_sig_js
    initial_function = jsi.extract_function(funcname)
  File "/usr/local/bin/youtube-dl/youtube_dl/jsinterp.py", line 241, in extract_function
    raise ExtractorError('Could not find JS function %r' % funcname)
ExtractorError: Could not find JS function u'gr'; 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.
 (caused by ExtractorError(u"Could not find JS function u'gr'; 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.",)); 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.

[phihag]

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