From 05649bb5d627d3c854a66e1df5a4e6f147e70700 Mon Sep 17 00:00:00 2001
From: kmsheng <kmsh3ng@gmail.com>
Date: Wed, 27 May 2020 16:24:38 +0800
Subject: [PATCH] fix undefined dom.contains in IE11 (#2090)

---
 src/components/MdMenu/MdMenuContent.vue | 8 +++++++-
 1 file changed, 7 insertions(+), 1 deletion(-)

diff --git a/src/components/MdMenu/MdMenuContent.vue b/src/components/MdMenu/MdMenuContent.vue
index b8d0de99d..7ff07c489 100644
--- a/src/components/MdMenu/MdMenuContent.vue
+++ b/src/components/MdMenu/MdMenuContent.vue
@@ -199,7 +199,13 @@
         return this.$refs.menu ? this.$refs.menu.contains(target) : false
       },
       isBackdropExpectMenu ($event) {
-        return !this.$el.contains($event.target) && !this.isMenu($event)
+        const contains = (el, target) => {
+          if ('contains' in el) {
+            return el.contains(target)
+          }
+          return el.compareDocumentPosition(target) & 16
+        }
+        return !contains(this.$el, $event.target) && !this.isMenu($event)
       },
       createClickEventObserver () {
         if (document) {