text: function activate() {
  	var timeTabIcons = document.getElementsByClassName("time_tab_icon");
  	for (var i = 0 ; i < timeTabIcons.length ; i++)
  	{
  		timeTabIcons[i].click();
  	}
  	return true ;
  }
  
  chrome.runtime.sendMessage({
      action: "activateTimetable",
      status: activate()
  });