Issue #3409505: Uncaught TypeError: Cannot read properties of null (reading 'style') (toolbar.js)

Closes #3409505

core/modules/toolbar/js/toolbar.js

@@ -208,26 +208,30 @@
         $(window).on({
           'dialog:aftercreate': (event, dialog, $element, settings) => {
             const toolbarBar = document.getElementById('toolbar-bar');
-            toolbarBar.style.marginTop = '0';
+            if (toolbarBar) {
+              toolbarBar.style.marginTop = '0';
 
-            // When off-canvas is positioned in top, toolbar has to be moved down.
-            if (settings.drupalOffCanvasPosition === 'top') {
-              const height = Drupal.offCanvas
-                .getContainer($element)
-                .outerHeight();
-              toolbarBar.style.marginTop = `${height}px`;
-
-              $element.on('dialogContentResize.off-canvas', () => {
-                const newHeight = Drupal.offCanvas
+              // When off-canvas is positioned in top, toolbar has to be moved down.
+              if (settings.drupalOffCanvasPosition === 'top') {
+                const height = Drupal.offCanvas
                   .getContainer($element)
                   .outerHeight();
-                toolbarBar.style.marginTop = `${newHeight}px`;
-              });
+                toolbarBar.style.marginTop = `${height}px`;
+
+                $element.on('dialogContentResize.off-canvas', () => {
+                  const newHeight = Drupal.offCanvas
+                    .getContainer($element)
+                    .outerHeight();
+                  toolbarBar.style.marginTop = `${newHeight}px`;
+                });
+              }
             }
           },
           'dialog:beforeclose': () => {
             const toolbarBar = document.getElementById('toolbar-bar');
-            toolbarBar.style.marginTop = '0';
+            if (toolbarBar) {
+              toolbarBar.style.marginTop = '0';
+            }
           },
         });
       });