    # File lib/termtter/system_extensions.rb, line 67
    def  open_browseropen_browser(url)
      found = case RUBY_PLATFORM.downcase
      when /linux/
        [['xdg-open'], ['x-www-browser'], ['firefox'], ['w3m', '-X']]
      when /darwin/
        [['open']]
      when /mswin(?!ce)|mingw|bccwin/
        [['start']]
      else
        [['xdg-open'], ['firefox'], ['w3m', '-X']]
      end.find do |cmd|
        system *(cmd.dup << url)
        $?.exitstatus != 127
      end
      if found
        # Kernel::__method__ is not suppoted in Ruby 1.8.6 or earlier.
        define_method(:open_browser) {|url| system *(found.dup << url) }
      else
        raise BrowserNotFound
      end
    end