diff --git a/core/modules/navigation/js/admin-toolbar-wrapper.js b/core/modules/navigation/js/admin-toolbar-wrapper.js
index 028e74ac7de..fa5403a3363 100644
--- a/core/modules/navigation/js/admin-toolbar-wrapper.js
+++ b/core/modules/navigation/js/admin-toolbar-wrapper.js
@@ -68,7 +68,7 @@
                 newState ? 'locked' : 'unlocked',
               );
 
-              doc.querySelector('.admin-toolbar').dispatchEvent(
+              doc.querySelector('.admin-toolbar')?.dispatchEvent(
                 new CustomEvent(SIDEBAR_CONTENT_EVENT, {
                   detail: {
                     state: newState,