code: function findByNodeName(el, nodeName) {
    if (!el.prop) { // not a jQuery or jqLite object -> wrap it
      el = angular.element(el)
    }
  
    if (el.prop('nodeName') === nodeName.toUpperCase()) {
      return el
    }
  
    const c = el.children()
    for (let i = 0; c && i < c.length; i++) {
      const node = findByNodeName(c[i], nodeName)
      if (node) {
        return node
      }
    }
  }
docs: recurse down a node tree to find a node with matching nodeName, for custom tags jQuery.find doesn't work in IE8