diff --git a/core/modules/ckeditor/js/ckeditor.admin.js b/core/modules/ckeditor/js/ckeditor.admin.js
index 9e6a8e6..330c600 100644
--- a/core/modules/ckeditor/js/ckeditor.admin.js
+++ b/core/modules/ckeditor/js/ckeditor.admin.js
@@ -362,7 +362,7 @@ Drupal.behaviors.ckeditorAdmin = {
     }
 
     if ($ckeditorToolbar.length) {
-      var $textareaWrapper = $ckeditorToolbar.find('.form-item-editor-settings-toolbar-buttons').hide();
+      var $textareaWrapper = $ckeditorToolbar.find('.form-item-editor-settings-toolbar-button-groups').hide();
       var $textarea = $textareaWrapper.find('textarea');
       var $toolbarAdmin = $(drupalSettings.ckeditor.toolbarAdmin);
       var sortableSettings = {
diff --git a/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/Editor/CKEditor.php b/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/Editor/CKEditor.php
index ee0a21f..1945536 100644
--- a/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/Editor/CKEditor.php
+++ b/core/modules/ckeditor/lib/Drupal/ckeditor/Plugin/Editor/CKEditor.php
@@ -148,10 +148,11 @@ public function settingsForm(array $form, array &$form_state, EditorEntity $edit
       ),
       '#attributes' => array('class' => array('ckeditor-toolbar-configuration')),
     );
-    $form['toolbar']['buttons'] = array(
+
+    $form['toolbar']['button_groups'] = array(
       '#type' => 'textarea',
       '#title' => t('Toolbar buttons'),
-      '#default_value' => json_encode($editor->settings['toolbar']),
+      '#default_value' => json_encode($editor->settings['toolbar']['rows']),
       '#attributes' => array('class' => array('ckeditor-toolbar-textarea')),
     );
 
@@ -225,7 +226,10 @@ public function settingsFormSubmit(array $form, array &$form_state) {
     // editor_form_filter_admin_format_submit().
     $toolbar_settings = &$form_state['values']['editor']['settings']['toolbar'];
 
-    $toolbar_settings = json_decode($toolbar_settings['buttons'], FALSE);
+    // The rows key is not built into the form structure, so decode the button
+    // groups data into this new key and remove the button_groups key.
+    $toolbar_settings['rows'] = json_decode($toolbar_settings['button_groups'], FALSE);
+    unset($toolbar_settings['button_groups']);
 
     // Remove the plugin settings' vertical tabs state; no need to save that.
     if (isset($form_state['values']['editor']['settings']['plugins'])) {
diff --git a/core/modules/ckeditor/lib/Drupal/ckeditor/Tests/CKEditorAdminTest.php b/core/modules/ckeditor/lib/Drupal/ckeditor/Tests/CKEditorAdminTest.php
index 22e9311..b375d03 100644
--- a/core/modules/ckeditor/lib/Drupal/ckeditor/Tests/CKEditorAdminTest.php
+++ b/core/modules/ckeditor/lib/Drupal/ckeditor/Tests/CKEditorAdminTest.php
@@ -115,7 +115,7 @@ function testAdmin() {
     // Ensure the toolbar buttons configuration value is initialized to the
     // expected default value.
     $expected_buttons_value = json_encode($expected_default_settings['toolbar']['rows']);
-    $this->assertFieldByName('editor[settings][toolbar][rows]', $expected_buttons_value);
+    $this->assertFieldByName('editor[settings][toolbar][button_groups]', $expected_buttons_value);
 
     // Ensure the styles textarea exists and is initialized empty.
     $styles_textarea = $this->xpath('//textarea[@name="editor[settings][plugins][stylescombo][styles]"]');
@@ -147,12 +147,13 @@ function testAdmin() {
     // done via drag and drop, but here we can only emulate the end result of
     // that interaction). Test multiple toolbar rows and a divider within a row.
     $this->drupalGet('admin/config/content/formats/manage/filtered_html');
-    $expected_settings['toolbar']['rows'][0][0] = array(
-      array('Undo', '|', 'Redo'),
-      array('JustifyCenter'),
+    $expected_settings['toolbar']['rows'][0][] = array(
+      'name' => 'Action history',
+      'items' => array('Undo', '|', 'Redo'),
+      array('JustifyCenter')
     );
     $edit = array(
-      'editor[settings][toolbar][rows]' => json_encode($expected_settings['toolbar']['rows']),
+      'editor[settings][toolbar][button_groups]' => json_encode($expected_settings['toolbar']['rows']),
     );
     $this->drupalPost(NULL, $edit, t('Save configuration'));
     $editor = entity_load('editor', 'filtered_html');
diff --git a/core/profiles/standard/config/editor.editor.basic_html.yml b/core/profiles/standard/config/editor.editor.basic_html.yml
index 89f42b5..e321d30 100644
--- a/core/profiles/standard/config/editor.editor.basic_html.yml
+++ b/core/profiles/standard/config/editor.editor.basic_html.yml
@@ -2,7 +2,7 @@ format: basic_html
 editor: ckeditor
 settings:
   toolbar:
-    buttons:
+    rows:
       -
         -
           name: Formatting