code: def _loading_thread(self, time):
          
          sleep(time)
          self.number = ""  # Clear URL selection number
          text = "Search: {}".format(self.search_string)
          if self.search_string:
              footer = 'search'
          else:
              footer = 'default'
              text = ""
          footerwid = urwid.AttrMap(urwid.Text(text), footer)
          self.top.footer = footerwid
          size = self.tui.get_cols_rows()
          self.draw_screen(size)
docs: Simple thread to wait <time> seconds after launching a URL or
          displaying a URL selection number, clearing the screen and clearing the
          footer loading message.