code: function () {
              var prop;
  
              removeEvent(this.chart.container, 'mouseleave', this.onContainerMouseLeave);
              if (!chartCount) {
                  removeEvent(doc, 'mouseup', this.onDocumentMouseUp);
                  removeEvent(doc, 'touchend', this.onDocumentTouchEnd);
              }
  
              // memory and CPU leak
              clearInterval(this.tooltipTimeout);
  
              for (prop in this) {
                  this[prop] = null;
              }
          }
docs: Destroys the Pointer object and disconnects DOM events.