old_contents: document.getElementById("id_logic_level_version").innerHTML="Business level version 2017.11.08.5";
  
  var canvas = document.getElementById("id_canvas");
  var context = canvas.getContext("2d");
  var rect = canvas.getBoundingClientRect();
  
  canvas.addEventListener("touchstart", on_touch_start);
  canvas.addEventListener("touchmove", on_touch_move);
  
  var touch_id = []; //this is a vector
  
  function generate_random_color()
  {
      var litere ="0123456789ABCDEF";
      var color = "#";
      for(i = 0; i < 6; i++)
              color += litere[Math.floor(Math.random() * 16)];
      
      return color;
  }
  
  function on_touch_start(e)
  {
      var touches = e.changedTouches;
      for (i = 0; i < e.changedTouches.length; i++)
      {
          touch_id.push(( id:touches[i].identifier, color:generate_random_color() ));
          
          context.beginPath();
          context.arc(touches[i].pageX - rect.left, touches[i].pageY - rect.top, 10, 0, 2 * Math.PI);
          context.strokeStyle = touch_id[touch.id.length - 1].color;
          context.fillStyle = touch_id[touch.id.length - 1].color;
          context.fill();
          context.stroke();
      }
      
  }
  
  function on_touch_move(e)
  {
      var touches = e.changedTouches;
      var color = "#FFFFFF";
      
       for (i = 0; i < e.changedTouches.length; i++)
      {
          for (j = 0; j < touch_id.length; j++)
              if (touches[i].identifier == touch_id[j].id){
                  color = touch_id[j].color;
                  break;
              }
                  
          context.beginPath();
          context.arc(touches[i].pageX - rect.left, touches[i].pageY - rect.top, 10, 0, 2 * Math.PI);
          context.strokeStyle = color;
          context.fillStyle = color;
          context.fill();
          context.stroke();
      }
      
  }
new_contents: document.getElementById("id_logic_level_version").innerHTML="Business level version 2017.11.08.5";
  
  var canvas = document.getElementById("id_canvas");
  var context = canvas.getContext("2d");
  var rect = canvas.getBoundingClientRect();
  
  canvas.addEventListener("touchstart", on_touch_start);
  canvas.addEventListener("touchmove", on_touch_move);
  
  var touch_id = []; //this is a vector
  
  function generate_random_color()
  {
      var litere ="0123456789ABCDEF";
      var color = "#";
      for(i = 0; i < 6; i++)
              color += litere[Math.floor(Math.random() * 16)];
      
      return color;
  }
  
  function on_touch_start(e)
  {
      var touches = e.changedTouches;
      for (i = 0; i < e.changedTouches.length; i++)
      {
          touch_id.push({ id:touches[i].identifier, color:generate_random_color() });
          
          context.beginPath();
          context.arc(touches[i].pageX - rect.left, touches[i].pageY - rect.top, 10, 0, 2 * Math.PI);
          context.strokeStyle = touch_id[touch.id.length - 1].color;
          context.fillStyle = touch_id[touch.id.length - 1].color;
          context.fill();
          context.stroke();
      }
      
  }
  
  function on_touch_move(e)
  {
      var touches = e.changedTouches;
      var color = "#FFFFFF";
      
       for (i = 0; i < e.changedTouches.length; i++)
      {
          for (j = 0; j < touch_id.length; j++)
              if (touches[i].identifier == touch_id[j].id){
                  color = touch_id[j].color;
                  break;
              }
                  
          context.beginPath();
          context.arc(touches[i].pageX - rect.left, touches[i].pageY - rect.top, 10, 0, 2 * Math.PI);
          context.strokeStyle = color;
          context.fillStyle = color;
          context.fill();
          context.stroke();
      }
      
  }
subject: Add "{}"