docs: def do_welcome(self):
          """Do setup when connected to server.
  
          - Join the primary channel.
          - Join the control channel.
  
          """
          self.rate_limited_send('join', self.config['core']['channel'])
          self.rate_limited_send('join', self.config['core']['ctrlchan'], self.config['auth']['ctrlkey'])
          # We use this to pick up info on admins who aren't currently in a channel.
          self.workers.defer(5, False, self.get_admins)
          extrachans = self.config['core']['extrachans']
          if extrachans:
              for chan in [x.strip() for x in extrachans.split(',')]:
                  self.rate_limited_send('join', chan)