old_contents: import urllib3
  import re
  
  from streamlink.plugin import Plugin
  from streamlink.plugin.api import http, validate
  from streamlink.plugin.api import useragents
  from streamlink.stream import HLSStream
  
  _url_re = re.compile(r"https?://(www\.)?ok\.ru/live/\d+")
  _vod_re = re.compile(r";(?P<hlsurl>[^;]+video\.m3u8)")
  
  _schema = validate.Schema(
      validate.transform(_vod_re.search),
      validate.any(
          None,
          validate.all(
              validate.get("hlsurl"),
              validate.url()
          )
      )
  )
  
  class OK_live(Plugin):
      """
      Support for ok.ru live stream: http://www.ok.ru/live/
      """
      @classmethod
      def can_handle_url(cls, url):
          return _url_re.match(url) is not None
  
      def _get_streams(self):
          headers = {
              'User-Agent': useragents.CHROME,
              'Referer': self.url
          }
  
          hls  = http.get(self.url, headers=headers, schema=_schema)
          return HLSStream.parse_variant_playlist(self.session, hls, headers=headers)
  
  
  __plugin__ = OK_live
new_contents: import re
  
  from streamlink.plugin import Plugin
  from streamlink.plugin.api import http, validate
  from streamlink.plugin.api import useragents
  from streamlink.stream import HLSStream
  
  _url_re = re.compile(r"https?://(www\.)?ok\.ru/live/\d+")
  _vod_re = re.compile(r";(?P<hlsurl>[^;]+video\.m3u8.+?)\\&quot;")
  
  _schema = validate.Schema(
      validate.transform(_vod_re.search),
      validate.any(
          None,
          validate.all(
              validate.get("hlsurl"),
              validate.url()
          )
      )
  )
  
  class OK_live(Plugin):
      """
      Support for ok.ru live stream: http://www.ok.ru/live/
      """
      @classmethod
      def can_handle_url(cls, url):
          return _url_re.match(url) is not None
  
      def _get_streams(self):
          headers = {
              'User-Agent': useragents.CHROME,
              'Referer': self.url
          }
  
          hls  = http.get(self.url, headers=headers, schema=_schema)
          if hls:
              hls = hls.replace(u'\\\\u0026', u'&')
          return HLSStream.parse_variant_playlist(self.session, hls, headers=headers)
  
  
  __plugin__ = OK_live
subject: fix <hlsurl> extraction