fix

components/menu/src/Divider.vue

@@ -1,6 +1,6 @@
 <script>
 export default {
-  name: 'Divider',
+  name: 'MenuDivider',
   props: {
     disabled: {
       type: Boolean,

components/menu/src/MenuMixin.js

@@ -135,7 +135,7 @@ export default {
 
     renderCommonMenuItem (child, i, subIndex, extraProps) {
       if (child.tag === undefined) { return child }
-      warning(['MenuItem', 'MenuItemGroup', 'SubMenu'].includes(getComponentName(child.componentOptions)),
+      warning(['MenuItem', 'MenuItemGroup', 'SubMenu', 'MenuDivider'].includes(getComponentName(child.componentOptions)),
         `Menu children not support ${getComponentName(child.componentOptions)}`,
       )
       const state = this.$data

components/menu/src/commonPropsType.js

@@ -22,5 +22,5 @@ export default {
   openTransitionName: PropTypes.string,
   forceSubMenuRender: PropTypes.bool,
   selectable: PropTypes.bool,
-  isRootMenu: PropTypes.bool,
+  isRootMenu: PropTypes.bool.def(true),
 }