diff --git a/src/core/event/sidebar.js b/src/core/event/sidebar.js
index f252f2b48..b15cb2afe 100644
--- a/src/core/event/sidebar.js
+++ b/src/core/event/sidebar.js
@@ -39,6 +39,7 @@ export function collapse(el) {
     if (
       target.nodeName === 'A' &&
       target.nextSibling &&
+      target.nextSibling.classList &&
       target.nextSibling.classList.contains('app-sub-sidebar')
     ) {
       dom.toggleClass(target.parentNode, 'collapse');