code: function () {
  
                      // Added by button implementation
                      removeEvent(wrapper.element, 'mouseenter');
                      removeEvent(wrapper.element, 'mouseleave');
  
                      if (text) {
                          text = text.destroy();
                      }
                      if (box) {
                          box = box.destroy();
                      }
                      // Call base implementation to destroy the rest
                      SVGElement.prototype.destroy.call(wrapper);
  
                      // Release local pointers (#1298)
                      wrapper = renderer = updateBoxSize = updateTextPadding = boxAttr = null;
                  }
docs: Destroy and release memory.