old_contents: (function (window, undefined) {
      var SpeechRecognition = window.webkitSpeechRecognition;
      var SpeechSynthesis = window.speechSynthesis;
  
      if (!SpeechRecognition || !SpeechSynthesis) {
          var supportWarning = document.getElementsByClassName('brower-support');
          supportWarning[0].style.display = 'block';
      }
  })(window);
  
new_contents: (function (window, undefined) {
      var Canvas = window.canvas;
  
      if (!Canvas) {
          var supportWarning = document.getElementsByClassName('brower-support');
          supportWarning[0].style.display = 'block';
      }
  })(window);
  
subject: Support class correction