Issue #3496541 by jurgenhaas, grimreaper, larowlan: Error when navigation...

Issue #3496541 by jurgenhaas, grimreaper, larowlan: Error when navigation JS is loaded for anonymous users

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,