code: function () {
              var wrapper = this,
                element = wrapper.element || {},
                shadows = wrapper.shadows,
                parentToClean = wrapper.renderer.isSVG && element.nodeName === 'SPAN' && wrapper.parentGroup,
                grandParent,
                key,
                i;
  
              // remove events
              element.onclick = element.onmouseout = element.onmouseover = element.onmousemove = element.point = null;
              stop(wrapper); // stop running animations
  
              if (wrapper.clipPath) {
                  wrapper.clipPath = wrapper.clipPath.destroy();
              }
  
              // Destroy stops in case this is a gradient object
              if (wrapper.stops) {
                  for (i = 0; i < wrapper.stops.length; i++) {
                      wrapper.stops[i] = wrapper.stops[i].destroy();
                  }
                  wrapper.stops = null;
              }
  
              // remove element
              wrapper.safeRemoveChild(element);
  
              // destroy shadows
              if (shadows) {
                  each(shadows, function (shadow) {
                      wrapper.safeRemoveChild(shadow);
                  });
              }
  
              // In case of useHTML, clean up empty containers emulating SVG groups (#1960, #2393, #2697).
              while (parentToClean && parentToClean.div && parentToClean.div.childNodes.length === 0) {
                  grandParent = parentToClean.parentGroup;
                  wrapper.safeRemoveChild(parentToClean.div);
                  delete parentToClean.div;
                  parentToClean = grandParent;
              }
  
              // remove from alignObjects
              if (wrapper.alignTo) {
                  erase(wrapper.renderer.alignedObjects, wrapper);
              }
  
              for (key in wrapper) {
                  delete wrapper[key];
              }
  
              return null;
          }
docs: Destroy the element and element wrapper