diff --git a/static/menu.js b/static/menu.js
index 155e5b1f6..4d63de4ee 100644
--- a/static/menu.js
+++ b/static/menu.js
@@ -281,7 +281,10 @@
                 e.preventDefault();
                 e.stopPropagation();
             }
-        } else if (e.target.parentNode.classList.contains("pure-menu-has-children")) {
+        } else if (e.target.parentNode &&
+            e.target.parentNode.classList &&
+            e.target.parentNode.classList.contains("pure-menu-has-children")
+        ) {
             switch (e.key.toLowerCase()) {
                 case "arrowdown":
                 case "down":