diff --git a/core/modules/ckeditor/ckeditor.libraries.yml b/core/modules/ckeditor/ckeditor.libraries.yml
index 5b937e8..5aa937f 100644
--- a/core/modules/ckeditor/ckeditor.libraries.yml
+++ b/core/modules/ckeditor/ckeditor.libraries.yml
@@ -23,7 +23,15 @@ drupal.ckeditor.plugins.drupalimagecaption:
 drupal.ckeditor.admin:
   version: VERSION
   js:
+    # Core.
     js/ckeditor.admin.js: {}
+    # Models.
+    js/models/Model.js: {}
+    # Views.
+    js/views/AuralView.js: {}
+    js/views/KeyboardView.js: {}
+    js/views/ControllerView.js: {}
+    js/views/VisualView.js: {}
   css:
     theme:
       css/ckeditor.admin.css: {}
diff --git a/core/modules/ckeditor/js/ckeditor.admin.js b/core/modules/ckeditor/js/ckeditor.admin.js
index efd2b24..54887d1 100644
--- a/core/modules/ckeditor/js/ckeditor.admin.js
+++ b/core/modules/ckeditor/js/ckeditor.admin.js
@@ -26,7 +26,7 @@
         $configurationForm.append(drupalSettings.ckeditor.toolbarAdmin);
 
         // Create a configuration model.
-        var model = Drupal.ckeditor.models.configurationModel = new Drupal.ckeditor.ConfigurationModel({
+        var model = Drupal.ckeditor.models.Model = new Drupal.ckeditor.Model({
           $textarea: $textarea,
           activeEditorConfig: JSON.parse($textarea.val()),
           hiddenEditorConfig: drupalSettings.ckeditor.hiddenCKEditorConfig
@@ -38,10 +38,10 @@
           el: $('.ckeditor-toolbar-configuration')
         };
         Drupal.ckeditor.views = {
-          controller: new Drupal.ckeditor.ConfigurationController(viewDefaults),
-          visualView: new Drupal.ckeditor.ConfigurationVisualView(viewDefaults),
-          keyboardView: new Drupal.ckeditor.ConfigurationKeyboardView(viewDefaults),
-          auralView: new Drupal.ckeditor.ConfigurationAuralView(viewDefaults)
+          controller: new Drupal.ckeditor.ControllerView(viewDefaults),
+          visualView: new Drupal.ckeditor.VisualView(viewDefaults),
+          keyboardView: new Drupal.ckeditor.KeyboardView(viewDefaults),
+          auralView: new Drupal.ckeditor.AuralView(viewDefaults)
         };
       }
     },
@@ -56,8 +56,8 @@
       // all editor features will be removed, so any reactions from filters will
       // be undone.
       var $configurationForm = $(context).find('.ckeditor-toolbar-configuration.ckeditor-configuration-processed');
-      if ($configurationForm.length && Drupal.ckeditor.models && Drupal.ckeditor.models.configurationModel) {
-        var config = Drupal.ckeditor.models.configurationModel.toJSON().activeEditorConfig;
+      if ($configurationForm.length && Drupal.ckeditor.models && Drupal.ckeditor.models.Model) {
+        var config = Drupal.ckeditor.models.Model.toJSON().activeEditorConfig;
         var buttons = Drupal.ckeditor.views.controller.getButtonList(config);
         var $activeToolbar = $('.ckeditor-toolbar-configuration').find('.ckeditor-toolbar-active');
         for (var i = 0; i < buttons.length; i++) {
@@ -79,1129 +79,52 @@
     models: {},
 
     /**
-     * Backbone model for the CKEditor toolbar configuration state.
-     */
-    ConfigurationModel: Backbone.Model.extend({
-      defaults: {
-        // The CKEditor configuration that is being manipulated through the UI.
-        activeEditorConfig: null,
-        // The textarea that contains the serialized representation of the active
-        // CKEditor configuration.
-        $textarea: null,
-        // Tracks whether the active toolbar DOM structure has been changed. When
-        // true, activeEditorConfig needs to be updated, and when that is updated,
-        // $textarea will also be updated.
-        isDirty: false,
-        // The configuration for the hidden CKEditor instance that is used to build
-        // the features metadata.
-        hiddenEditorConfig: null,
-        // A hash, keyed by a feature name, that details CKEditor plugin features.
-        featuresMetadata: null,
-        // Whether the button group names are currently visible.
-        groupNamesVisible: false
-      },
-      sync: function () {
-        // Push the settings into the textarea.
-        this.get('$textarea').val(JSON.stringify(this.get('activeEditorConfig')));
-      }
-    }),
-
-    /**
-     * Backbone View acting as a controller for CKEditor toolbar configuration.
+     * Translates a change in CKEditor config DOM structure into the config model.
+     *
+     * If the button is moved within an existing group, the DOM structure is simply
+     * translated to a configuration model. If the button is moved into a new group
+     * placeholder, then a process is launched to name that group before the button
+     * move is translated into configuration.
+     *
+     * @param Backbone.View view
+     *   The Backbone View that invoked this function.
+     * @param jQuery $button
+     *   A jQuery set that contains an li element that wraps a button element.
+     * @param function callback
+     *   A callback to invoke after the button group naming modal dialog has been
+     *   closed.
      */
-    ConfigurationController: Backbone.View.extend({
-
-      events: {},
-
-      /**
-       * {@inheritdoc}
-       */
-      initialize: function () {
-        this.getCKEditorFeatures(this.model.get('hiddenEditorConfig'), this.disableFeaturesDisallowedByFilters.bind(this));
-
-        // Push the active editor configuration to the textarea.
-        this.model.listenTo(this.model, 'change:activeEditorConfig', this.model.sync);
-        this.listenTo(this.model, 'change:isDirty', this.parseEditorDOM);
-      },
-
-      /**
-       * Converts the active toolbar DOM structure to an object representation.
-       *
-       * @param Drupal.ckeditor.ConfigurationModel model
-       *   The state model for the CKEditor configuration.
-       * @param Boolean isDirty
-       *   Tracks whether the active toolbar DOM structure has been changed.
-       *   isDirty is toggled back to false in this method.
-       * @param Object options
-       *   An object that includes:
-       *   - Boolean broadcast: (optional) A flag that controls whether a
-       *     CKEditorToolbarChanged event should be fired for configuration
-       *     changes.
-       */
-      parseEditorDOM: function (model, isDirty, options) {
-        if (isDirty) {
-          var currentConfig = this.model.get('activeEditorConfig');
-
-          // Process the rows.
-          var rows = [];
-          this.$el
-            .find('.ckeditor-active-toolbar-configuration')
-            .children('.ckeditor-row').each(function () {
-              var groups = [];
-              // Process the button groups.
-              $(this).find('.ckeditor-toolbar-group').each(function () {
-                var $group = $(this);
-                var $buttons = $group.find('.ckeditor-button');
-                if ($buttons.length) {
-                  var group = {
-                    name: $group.attr('data-drupal-ckeditor-toolbar-group-name'),
-                    items: []
-                  };
-                  $group.find('.ckeditor-button, .ckeditor-multiple-button').each(function () {
-                    group.items.push($(this).attr('data-drupal-ckeditor-button-name'));
-                  });
-                  groups.push(group);
-                }
-              });
-              if (groups.length) {
-                rows.push(groups);
-              }
-            });
-          this.model.set('activeEditorConfig', rows);
-          // Mark the model as clean. Whether or not the sync to the textfield
-          // occurs depends on the activeEditorConfig attribute firing a change
-          // event. The DOM has at least been processed and posted, so as far as
-          // the model is concerned, it is clean.
-          this.model.set('isDirty', false);
-
-          // Determine whether we should trigger an event.
-          if (options.broadcast !== false) {
-            var prev = this.getButtonList(currentConfig);
-            var next = this.getButtonList(rows);
-            if (prev.length !== next.length) {
-              this.$el
-                .find('.ckeditor-toolbar-active')
-                .trigger('CKEditorToolbarChanged', [
-                  (prev.length < next.length) ? 'added' : 'removed',
-                  _.difference(_.union(prev, next), _.intersection(prev, next))[0]
-                ]);
-            }
-          }
-        }
-      },
-
-      /**
-       * Asynchronously retrieve the metadata for all available CKEditor features.
-       *
-       * In order to get a list of all features needed by CKEditor, we create a
-       * hidden CKEditor instance, then check the CKEditor's "allowedContent"
-       * filter settings. Because creating an instance is expensive, a callback
-       * must be provided that will receive a hash of Drupal.EditorFeature
-       * features keyed by feature (button) name.
-       *
-       * @param Object CKEditorConfig
-       *   An object that represents the configuration settings for a CKEditor
-       *   editor component.
-       * @param Function callback
-       *   A function to invoke when the instanceReady event is fired by the
-       *   CKEditor object.
-       */
-      getCKEditorFeatures: function (CKEditorConfig, callback) {
-        var getProperties = function (CKEPropertiesList) {
-          return (_.isObject(CKEPropertiesList)) ? _.keys(CKEPropertiesList) : [];
-        };
-
-        var convertCKERulesToEditorFeature = function (feature, CKEFeatureRules) {
-          for (var i = 0; i < CKEFeatureRules.length; i++) {
-            var CKERule = CKEFeatureRules[i];
-            var rule = new Drupal.EditorFeatureHTMLRule();
-
-            // Tags.
-            var tags = getProperties(CKERule.elements);
-            rule.required.tags = (CKERule.propertiesOnly) ? [] : tags;
-            rule.allowed.tags = tags;
-            // Attributes.
-            rule.required.attributes = getProperties(CKERule.requiredAttributes);
-            rule.allowed.attributes = getProperties(CKERule.attributes);
-            // Styles.
-            rule.required.styles = getProperties(CKERule.requiredStyles);
-            rule.allowed.styles = getProperties(CKERule.styles);
-            // Classes.
-            rule.required.classes = getProperties(CKERule.requiredClasses);
-            rule.allowed.classes = getProperties(CKERule.classes);
-            // Raw.
-            rule.raw = CKERule;
-
-            feature.addHTMLRule(rule);
-          }
-        };
-
-        // Create hidden CKEditor with all features enabled, retrieve metadata.
-        // @see \Drupal\ckeditor\Plugin\Editor\CKEditor::settingsForm.
-        var hiddenCKEditorID = 'ckeditor-hidden';
-        if (CKEDITOR.instances[hiddenCKEditorID]) {
-          CKEDITOR.instances[hiddenCKEditorID].destroy(true);
-        }
-        // Load external plugins, if any.
-        var hiddenEditorConfig = this.model.get('hiddenEditorConfig');
-        if (hiddenEditorConfig.drupalExternalPlugins) {
-          var externalPlugins = hiddenEditorConfig.drupalExternalPlugins;
-          for (var pluginName in externalPlugins) {
-            if (externalPlugins.hasOwnProperty(pluginName)) {
-              CKEDITOR.plugins.addExternal(pluginName, externalPlugins[pluginName], '');
-            }
-          }
-        }
-        CKEDITOR.inline($('#' + hiddenCKEditorID).get(0), CKEditorConfig);
-
-        // Once the instance is ready, retrieve the allowedContent filter rules
-        // and convert them to Drupal.EditorFeature objects.
-        CKEDITOR.once('instanceReady', function (e) {
-          if (e.editor.name === hiddenCKEditorID) {
-            // First collect all CKEditor allowedContent rules.
-            var CKEFeatureRulesMap = {};
-            var rules = e.editor.filter.allowedContent;
-            var rule, name;
-            for (var i = 0; i < rules.length; i++) {
-              rule = rules[i];
-              name = rule.featureName || ':(';
-              if (!CKEFeatureRulesMap[name]) {
-                CKEFeatureRulesMap[name] = [];
-              }
-              CKEFeatureRulesMap[name].push(rule);
-            }
-
-            // Now convert these to Drupal.EditorFeature objects.
-            var features = {};
-            for (var featureName in CKEFeatureRulesMap) {
-              if (CKEFeatureRulesMap.hasOwnProperty(featureName)) {
-                var feature = new Drupal.EditorFeature(featureName);
-                convertCKERulesToEditorFeature(feature, CKEFeatureRulesMap[featureName]);
-                features[featureName] = feature;
-              }
-            }
+    registerButtonMove: function(view, $button, callback) {
+      var $group = $button.closest('.ckeditor-toolbar-group');
 
-            callback(features);
-          }
-        });
-      },
-
-      /**
-       * Retrieves the feature for a given button from featuresMetadata. Returns
-       * false if the given button is in fact a divider.
-       *
-       * @param String button
-       *   The name of a CKEditor button.
-       * @return Object
-       *   The feature metadata object for a button.
-       */
-      getFeatureForButton: function (button) {
-        // Return false if the button being added is a divider.
-        if (button === '-') {
-          return false;
-        }
-
-        // Get a Drupal.editorFeature object that contains all metadata for
-        // the feature that was just added or removed. Not every feature has
-        // such metadata.
-        var featureName = button.toLowerCase();
-        var featuresMetadata = this.model.get('featuresMetadata');
-        if (!featuresMetadata[featureName]) {
-          featuresMetadata[featureName] = new Drupal.EditorFeature(featureName);
-          this.model.set('featuresMetadata', featuresMetadata);
-        }
-        return featuresMetadata[featureName];
-      },
-
-      /**
-       * Checks buttons against filter settings; disables disallowed buttons.
-       *
-       * @param Object features
-       *   A map of Drupal.EditorFeature objects.
-       */
-      disableFeaturesDisallowedByFilters: function (features) {
-        this.model.set('featuresMetadata', features);
-
-        // Ensure that toolbar configuration changes are broadcast.
-        this.broadcastConfigurationChanges(this.$el);
-
-        // Initialization: not all of the default toolbar buttons may be allowed
-        // by the current filter settings. Remove any of the default toolbar
-        // buttons that require more permissive filter settings. The remaining
-        // default toolbar buttons are marked as "added".
-        var existingButtons = [];
-        // Loop through each button group after flattening the groups from the
-        // toolbar row arrays.
-        for (var i = 0, buttonGroups = _.flatten(this.model.get('activeEditorConfig')); i < buttonGroups.length; i++) {
-          // Pull the button names from each toolbar button group.
-          for (var k = 0, buttons = buttonGroups[i].items; k < buttons.length; k++) {
-            existingButtons.push(buttons[k]);
-          }
-        }
-        // Remove duplicate buttons.
-        existingButtons = _.unique(existingButtons);
-        // Prepare the active toolbar and available-button toolbars.
-        for (i = 0; i < existingButtons.length; i++) {
-          var button = existingButtons[i];
-          var feature = this.getFeatureForButton(button);
-          // Skip dividers.
-          if (feature === false) {
-            continue;
-          }
-
-          if (Drupal.editorConfiguration.featureIsAllowedByFilters(feature)) {
-            // Existing toolbar buttons are in fact "added features".
-            this.$el.find('.ckeditor-toolbar-active').trigger('CKEditorToolbarChanged', ['added', existingButtons[i]]);
-          }
-          else {
-            // Move the button element from the active the active toolbar to the
-            // list of available buttons.
-            $('.ckeditor-toolbar-active li[data-drupal-ckeditor-button-name="' + button + '"]')
-              .detach()
-              .appendTo('.ckeditor-toolbar-disabled > .ckeditor-toolbar-available > ul');
-            // Update the toolbar value field.
-            this.model.set({'isDirty': true}, {broadcast: false});
-          }
-        }
-      },
+      // If dropped in a placeholder button group, the user must name it.
+      if ($group.hasClass('placeholder')) {
 
-      /**
-       * Sets up broadcasting of CKEditor toolbar configuration changes.
-       *
-       * @param jQuery $ckeditorToolbar
-       *   The active toolbar DOM element wrapped in jQuery.
-       */
-      broadcastConfigurationChanges: function ($ckeditorToolbar) {
-        var view = this;
-        var hiddenEditorConfig = this.model.get('hiddenEditorConfig');
-        var featuresMetadata = this.model.get('featuresMetadata');
-        var getFeatureForButton = this.getFeatureForButton.bind(this);
-        var getCKEditorFeatures = this.getCKEditorFeatures.bind(this);
-        $ckeditorToolbar
-          .find('.ckeditor-toolbar-active')
-          // Listen for CKEditor toolbar configuration changes. When a button is
-          // added/removed, call an appropriate Drupal.editorConfiguration method.
-          .on('CKEditorToolbarChanged.ckeditorAdmin', function (event, action, button) {
-            var feature = getFeatureForButton(button);
-
-            // Early-return if the button being added is a divider.
-            if (feature === false) {
+          if (view.isProcessing) {
               return;
-            }
-
-            // Trigger a standardized text editor configuration event to indicate
-            // whether a feature was added or removed, so that filters can react.
-            var configEvent = (action === 'added') ? 'addedFeature' : 'removedFeature';
-            Drupal.editorConfiguration[configEvent](feature);
-          })
-          // Listen for CKEditor plugin settings changes. When a plugin setting is
-          // changed, rebuild the CKEditor features metadata.
-          .on('CKEditorPluginSettingsChanged.ckeditorAdmin', function (event, settingsChanges) {
-            // Update hidden CKEditor configuration.
-            for (var key in settingsChanges) {
-              if (settingsChanges.hasOwnProperty(key)) {
-                hiddenEditorConfig[key] = settingsChanges[key];
-              }
-            }
-
-            // Retrieve features for the updated hidden CKEditor configuration.
-            getCKEditorFeatures(hiddenEditorConfig, function (features) {
-              // Trigger a standardized text editor configuration event for each
-              // feature that was modified by the configuration changes.
-              for (var name in features) {
-                if (features.hasOwnProperty(name)) {
-                  var feature = features[name];
-                  if (featuresMetadata.hasOwnProperty(name) && !_.isEqual(featuresMetadata[name], feature)) {
-                    Drupal.editorConfiguration.modifiedFeature(feature);
-                  }
-                }
-              }
-              // Update the CKEditor features metadata.
-              view.model.set('featuresMetadata', features);
-            });
-          });
-      },
-
-      /**
-       * Returns the list of buttons from an editor configuration.
-       *
-       * @param Object config
-       *   A CKEditor configuration object.
-       * @return Array
-       *   A list of buttons in the CKEditor configuration.
-       */
-      getButtonList: function (config) {
-        var buttons = [];
-        // Remove the rows
-        config = _.flatten(config);
-
-        // Loop through the button groups and pull out the buttons.
-        config.forEach(function (group) {
-          group.items.forEach(function (button) {
-            buttons.push(button);
-          });
-        });
-
-        // Remove the dividing elements if any.
-        return _.without(buttons, '-');
-      }
-    }),
-
-    /**
-     * Backbone View for CKEditor toolbar configuration; visual UX.
-     */
-    ConfigurationVisualView: Backbone.View.extend({
-
-      events: {
-        'click .ckeditor-toolbar-group-name': 'onGroupNameClick',
-        'click .ckeditor-groupnames-toggle': 'onGroupNamesToggleClick',
-        'click .ckeditor-add-new-group button': 'onAddGroupButtonClick'
-      },
-
-      /**
-       * {@inheritdoc}
-       */
-      initialize: function () {
-        this.listenTo(this.model, 'change:isDirty change:groupNamesVisible', this.render);
-
-        // Add a toggle for the button group names.
-        $(Drupal.theme('ckeditorButtonGroupNamesToggle'))
-          .prependTo(this.$el.find('#ckeditor-active-toolbar').parent());
-
-        this.render();
-      },
-
-      /**
-       * {@inheritdoc}
-       */
-      render: function (model, value, changedAttributes) {
-        this.insertPlaceholders();
-        this.applySorting();
-
-        // Toggle button group names.
-        var groupNamesVisible = this.model.get('groupNamesVisible');
-        // If a button was just placed in the active toolbar, ensure that the
-        // button group names are visible.
-        if (changedAttributes && changedAttributes.changes && changedAttributes.changes.isDirty) {
-          this.model.set({groupNamesVisible: true}, {silent: true});
-          groupNamesVisible = true;
-        }
-        this.$el.find('[data-toolbar="active"]').toggleClass('ckeditor-group-names-are-visible', groupNamesVisible);
-        this.$el.find('.ckeditor-groupnames-toggle')
-          .text((groupNamesVisible) ? Drupal.t('Hide group names') : Drupal.t('Show group names'))
-          .attr('aria-pressed', groupNamesVisible);
-
-        return this;
-      },
-
-      /**
-       * Handles clicks to a button group name.
-       *
-       * @param jQuery.Event event
-       */
-      onGroupNameClick: function (event) {
-        var $group = $(event.currentTarget).closest('.ckeditor-toolbar-group');
-        openGroupNameDialog(this, $group);
-
-        event.stopPropagation();
-        event.preventDefault();
-      },
-
-      /**
-       * Handles clicks on the button group names toggle button.
-       */
-      onGroupNamesToggleClick: function (event) {
-        this.model.set('groupNamesVisible', !this.model.get('groupNamesVisible'));
-        event.preventDefault();
-      },
-
-      /**
-       * Prompts the user to provide a name for a new button group; inserts it.
-       *
-       * @param jQuery.Event event
-       */
-      onAddGroupButtonClick: function (event) {
-
-        /**
-         * Inserts a new button if the openGroupNameDialog function returns true.
-         *
-         * @param Boolean success
-         *   A flag that indicates if the user created a new group (true) or
-         *   canceled out of the dialog (false).
-         * @param jQuery $group
-         *   A jQuery DOM fragment that represents the new button group. It has
-         *   not been added to the DOM yet.
-         */
-        function insertNewGroup(success, $group) {
-          if (success) {
-            $group.appendTo($(event.currentTarget).closest('.ckeditor-row').children('.ckeditor-toolbar-groups'));
-            // Focus on the new group.
-            $group.trigger('focus');
-          }
-        }
-
-        // Pass in a DOM fragment of a placeholder group so that the new group
-        // name can be applied to it.
-        openGroupNameDialog(this, $(Drupal.theme('ckeditorToolbarGroup')), insertNewGroup);
-
-        event.preventDefault();
-      },
-
-      /**
-       * Handles jQuery Sortable stop sort of a button group.
-       *
-       * @param jQuery.Event event
-       * @param Object ui
-       *   A jQuery.ui.sortable argument that contains information about the
-       *   elements involved in the sort action.
-       */
-      endGroupDrag: function (event, ui) {
-        var view = this;
-        registerGroupMove(this, ui.item, function (success) {
-          if (!success) {
-            // Cancel any sorting in the configuration area.
-            view.$el.find('.ckeditor-toolbar-configuration').find('.ui-sortable').sortable('cancel');
           }
-        });
-      },
+          view.isProcessing = true;
 
-      /**
-       * Handles jQuery Sortable start sort of a button.
-       *
-       * @param jQuery.Event event
-       * @param Object ui
-       *   A jQuery.ui.sortable argument that contains information about the
-       *   elements involved in the sort action.
-       */
-      startButtonDrag: function (event, ui) {
-        this.$el.find('a:focus').trigger('blur');
-
-        // Show the button group names as soon as the user starts dragging.
-        this.model.set('groupNamesVisible', true);
-      },
-
-      /**
-       * Handles jQuery Sortable stop sort of a button.
-       *
-       * @param jQuery.Event event
-       * @param Object ui
-       *   A jQuery.ui.sortable argument that contains information about the
-       *   elements involved in the sort action.
-       */
-      endButtonDrag: function (event, ui) {
-        var view = this;
-        registerButtonMove(this, ui.item, function (success) {
-          if (!success) {
-            // Cancel any sorting in the configuration area.
-            view.$el.find('.ui-sortable').sortable('cancel');
-          }
-          // Refocus the target button so that the user can continue from a known
-          // place.
-          ui.item.find('a').trigger('focus');
-        });
-      },
-
-      /**
-       * Invokes jQuery.sortable() on new buttons and groups in a CKEditor config.
-       */
-      applySorting: function () {
-        // Make the buttons sortable.
-        this.$el.find('.ckeditor-buttons').not('.ui-sortable').sortable({
-          // Change this to .ckeditor-toolbar-group-buttons.
-          connectWith: '.ckeditor-buttons',
-          placeholder: 'ckeditor-button-placeholder',
-          forcePlaceholderSize: true,
-          tolerance: 'pointer',
-          cursor: 'move',
-          start: this.startButtonDrag.bind(this),
-          // Sorting within a sortable.
-          stop: this.endButtonDrag.bind(this)
-        }).disableSelection();
-
-        // Add the drag and drop functionality to button groups.
-        this.$el.find('.ckeditor-toolbar-groups').not('.ui-sortable').sortable({
-          connectWith: '.ckeditor-toolbar-groups',
-          cancel: '.ckeditor-add-new-group',
-          placeholder: 'ckeditor-toolbar-group-placeholder',
-          forcePlaceholderSize: true,
-          cursor: 'move',
-          stop: this.endGroupDrag.bind(this)
-        });
-
-        // Add the drag and drop functionality to buttons.
-        this.$el.find('.ckeditor-multiple-buttons li').draggable({
-          connectToSortable: '.ckeditor-toolbar-active .ckeditor-buttons',
-          helper: 'clone'
-        });
-      },
-
-      /**
-       * Wraps the invocation of methods to insert blank groups and rows.
-       */
-      insertPlaceholders: function () {
-        this.insertPlaceholderRow();
-        this.insertNewGroupButtons();
-      },
-
-      /**
-       * Inserts a blank row at the bottom of the CKEditor configuration.
-       */
-      insertPlaceholderRow: function () {
-        var $rows = this.$el.find('.ckeditor-row');
-        // Add a placeholder row. to the end of the list if one does not exist.
-        if (!$rows.eq(-1).hasClass('placeholder')) {
-          this.$el
-            .find('.ckeditor-toolbar-active')
-            .children('.ckeditor-active-toolbar-configuration')
-            .append(Drupal.theme('ckeditorRow'));
-        }
-        // Update the $rows variable to include the new row.
-        $rows = this.$el.find('.ckeditor-row');
-        // Remove blank rows except the last one.
-        var len = $rows.length;
-        $rows.filter(function (index, row) {
-          // Do not remove the last row.
-          if (index + 1 === len) {
-            return false;
-          }
-          return $(row).find('.ckeditor-toolbar-group').not('.placeholder').length === 0;
-        })
-          // Then get all rows that are placeholders and remove them.
-          .remove();
-      },
-
-      /**
-       * Inserts a button in each row that will add a new CKEditor button group.
-       */
-      insertNewGroupButtons: function () {
-        // Insert an add group button to each row.
-        this.$el.find('.ckeditor-row').each(function () {
-          var $row = $(this);
-          var $groups = $row.find('.ckeditor-toolbar-group');
-          var $button = $row.find('.ckeditor-add-new-group');
-          if ($button.length === 0) {
-            $row.children('.ckeditor-toolbar-groups').append(Drupal.theme('ckeditorNewButtonGroup'));
-          }
-          // If a placeholder group exists, make sure it's at the end of the row.
-          else if (!$groups.eq(-1).hasClass('ckeditor-add-new-group')) {
-            $button.appendTo($row.children('.ckeditor-toolbar-groups'));
-          }
-        });
+          openGroupNameDialog(view, $group, callback);
       }
-    }),
-
-    /**
-     * Backbone View for CKEditor toolbar configuration; keyboard UX.
-     */
-    ConfigurationKeyboardView: Backbone.View.extend({
-
-      /**
-       * {@inheritdoc}
-       */
-      initialize: function () {
-        // Add keyboard arrow support.
-        this.$el.on('keydown.ckeditor', '.ckeditor-buttons a, .ckeditor-multiple-buttons a', this.onPressButton.bind(this));
-        this.$el.on('keydown.ckeditor', '[data-drupal-ckeditor-type="group"]', this.onPressGroup.bind(this));
-      },
-
-      /**
-       * {@inheritdoc}
-       */
-      render: function () {},
-
-      /**
-       * Handles keypresses on a CKEditor configuration button.
-       *
-       * @param jQuery.Event event
-       */
-      onPressButton: function (event) {
-        var upDownKeys = [
-          38, // Up arrow.
-          63232, // Safari up arrow.
-          40, // Down arrow.
-          63233 // Safari down arrow.
-        ];
-        var leftRightKeys = [
-          37, // Left arrow.
-          63234, // Safari left arrow.
-          39, // Right arrow.
-          63235 // Safari right arrow.
-        ];
-
-        // Respond to an enter key press. Prevent the bubbling of the enter key
-        // press to the button group parent element.
-        if (event.keyCode === 13) {
-          event.stopPropagation();
-        }
-
-        // Only take action when a direction key is pressed.
-        if (_.indexOf(_.union(upDownKeys, leftRightKeys), event.keyCode) > -1) {
-          var view = this;
-          var $target = $(event.currentTarget);
-          var $button = $target.parent();
-          var $container = $button.parent();
-          var $group = $button.closest('.ckeditor-toolbar-group');
-          var $row = $button.closest('.ckeditor-row');
-          var containerType = $container.data('drupal-ckeditor-button-sorting');
-          var $availableButtons = this.$el.find('[data-drupal-ckeditor-button-sorting="source"]');
-          var $activeButtons = this.$el.find('.ckeditor-toolbar-active');
-          // The current location of the button, just in case it needs to be put
-          // back.
-          var $originalGroup = $group;
-          var dir;
-
-          // Move available buttons between their container and the active toolbar.
-          if (containerType === 'source') {
-            // Move the button to the active toolbar configuration when the down or
-            // up keys are pressed.
-            if (_.indexOf([40, 63233], event.keyCode) > -1) {
-              // Move the button to the first row, first button group index
-              // position.
-              $activeButtons.find('.ckeditor-toolbar-group-buttons').eq(0).prepend($button);
-            }
-          }
-          else if (containerType === 'target') {
-            // Move buttons between sibling buttons in a group and between groups.
-            if (_.indexOf(leftRightKeys, event.keyCode) > -1) {
-              // Move left.
-              var $siblings = $container.children();
-              var index = $siblings.index($button);
-              if (_.indexOf([37, 63234], event.keyCode) > -1) {
-                // Move between sibling buttons.
-                if (index > 0) {
-                  $button.insertBefore($container.children().eq(index - 1));
-                }
-                // Move between button groups and rows.
-                else {
-                  // Move between button groups.
-                  $group = $container.parent().prev();
-                  if ($group.length > 0) {
-                    $group.find('.ckeditor-toolbar-group-buttons').append($button);
-                  }
-                  // Wrap between rows.
-                  else {
-                    $container.closest('.ckeditor-row').prev().find('.ckeditor-toolbar-group').not('.placeholder').find('.ckeditor-toolbar-group-buttons').eq(-1).append($button);
-                  }
-                }
-              }
-              // Move right.
-              else if (_.indexOf([39, 63235], event.keyCode) > -1) {
-                // Move between sibling buttons.
-                if (index < ($siblings.length - 1)) {
-                  $button.insertAfter($container.children().eq(index + 1));
-                }
-                // Move between button groups. Moving right at the end of a row
-                // will create a new group.
-                else {
-                  $container.parent().next().find('.ckeditor-toolbar-group-buttons').prepend($button);
-                }
-              }
-            }
-            // Move buttons between rows and the available button set.
-            else if (_.indexOf(upDownKeys, event.keyCode) > -1) {
-              dir = (_.indexOf([38, 63232], event.keyCode) > -1) ? 'prev' : 'next';
-              $row = $container.closest('.ckeditor-row')[dir]();
-              // Move the button back into the available button set.
-              if (dir === 'prev' && $row.length === 0) {
-                // If this is a divider, just destroy it.
-                if ($button.data('drupal-ckeditor-type') === 'separator') {
-                  $button
-                    .off()
-                    .remove();
-                  // Focus on the first button in the active toolbar.
-                  $activeButtons.find('.ckeditor-toolbar-group-buttons').eq(0).children().eq(0).children().trigger('focus');
-                }
-                // Otherwise, move it.
-                else {
-                  $availableButtons.prepend($button);
-                }
-              }
-              else {
-                $row.find('.ckeditor-toolbar-group-buttons').eq(0).prepend($button);
-              }
-            }
-          }
-          // Move dividers between their container and the active toolbar.
-          else if (containerType === 'dividers') {
-            // Move the button to the active toolbar configuration when the down or
-            // up keys are pressed.
-            if (_.indexOf([40, 63233], event.keyCode) > -1) {
-              // Move the button to the first row, first button group index
-              // position.
-              $button = $button.clone(true);
-              $activeButtons.find('.ckeditor-toolbar-group-buttons').eq(0).prepend($button);
-              $target = $button.children();
-            }
-          }
-
-          view = this;
-          // Attempt to move the button to the new toolbar position.
-          registerButtonMove(this, $button, function (result) {
-
-            // Put the button back if the registration failed.
-            // If the button was in a row, then it was in the active toolbar
-            // configuration. The button was probably placed in a new group, but
-            // that action was canceled.
-            if (!result && $originalGroup) {
-              $originalGroup.find('.ckeditor-buttons').append($button);
-            }
-            // Otherwise refresh the sortables to acknowledge the new button
-            // positions.
-            else {
-              view.$el.find('.ui-sortable').sortable('refresh');
-            }
-            // Refocus the target button so that the user can continue from a known
-            // place.
-            $target.trigger('focus');
-          });
-
-          event.preventDefault();
-          event.stopPropagation();
-        }
-      },
-
-      /**
-       * Handles keypresses on a CKEditor configuration group.
-       *
-       * @param jQuery.Event event
-       */
-      onPressGroup: function (event) {
-        var upDownKeys = [
-          38, // Up arrow.
-          63232, // Safari up arrow.
-          40, // Down arrow.
-          63233 // Safari down arrow.
-        ];
-        var leftRightKeys = [
-          37, // Left arrow.
-          63234, // Safari left arrow.
-          39, // Right arrow.
-          63235 // Safari right arrow.
-        ];
-
-        // Respond to an enter key press.
-        if (event.keyCode === 13) {
-          var view = this;
-          // Open the group renaming dialog in the next evaluation cycle so that
-          // this event can be cancelled and the bubbling wiped out. Otherwise,
-          // Firefox has issues because the page focus is shifted to the dialog
-          // along with the keydown event.
-          window.setTimeout(function () {
-            openGroupNameDialog(view, $(event.currentTarget));
-          }, 0);
-          event.preventDefault();
-          event.stopPropagation();
-        }
-
-        // Respond to direction key presses.
-        if (_.indexOf(_.union(upDownKeys, leftRightKeys), event.keyCode) > -1) {
-          var $group = $(event.currentTarget);
-          var $container = $group.parent();
-          var $siblings = $container.children();
-          var index, dir;
-          // Move groups between sibling groups.
-          if (_.indexOf(leftRightKeys, event.keyCode) > -1) {
-            index = $siblings.index($group);
-            // Move left between sibling groups.
-            if ((_.indexOf([37, 63234], event.keyCode) > -1)) {
-              if (index > 0) {
-                $group.insertBefore($siblings.eq(index - 1));
-              }
-              // Wrap between rows. Insert the group before the placeholder group
-              // at the end of the previous row.
-              else {
-                $group.insertBefore($container.closest('.ckeditor-row').prev().find('.ckeditor-toolbar-groups').children().eq(-1));
-              }
-            }
-            // Move right between sibling groups.
-            else if (_.indexOf([39, 63235], event.keyCode) > -1) {
-              // Move to the right if the next group is not a placeholder.
-              if (!$siblings.eq(index + 1).hasClass('placeholder')) {
-                $group.insertAfter($container.children().eq(index + 1));
-              }
-              // Wrap group between rows.
-              else {
-                $container.closest('.ckeditor-row').next().find('.ckeditor-toolbar-groups').prepend($group);
-              }
-            }
-
-          }
-          // Move groups between rows.
-          else if (_.indexOf(upDownKeys, event.keyCode) > -1) {
-            dir = (_.indexOf([38, 63232], event.keyCode) > -1) ? 'prev' : 'next';
-            $group.closest('.ckeditor-row')[dir]().find('.ckeditor-toolbar-groups').eq(0).prepend($group);
-          }
-
-          registerGroupMove(this, $group);
-          $group.trigger('focus');
-          event.preventDefault();
-          event.stopPropagation();
-        }
+      else {
+          view.model.set('isDirty', true);
+          callback(true);
       }
-    }),
+    },
 
     /**
-     * Backbone View for CKEditor toolbar configuration; aural UX (output only).
+     * Translates a change in CKEditor config DOM structure into the config model.
+     *
+     * Each row has a placeholder group at the end of the row. A user may not move
+     * an existing button group past the placeholder group at the end of a row.
+     *
+     * @param Backbone.View view
+     *   The Backbone View that invoked this function.
+     * @param jQuery $group
+     *   A jQuery set that contains an li element that wraps a group of buttons.
      */
-    ConfigurationAuralView: Backbone.View.extend({
-
-      events: {
-        'click .ckeditor-buttons a': 'announceButtonHelp',
-        'click .ckeditor-multiple-buttons a': 'announceSeparatorHelp',
-        'focus .ckeditor-button a': 'onFocus',
-        'focus .ckeditor-button-separator a': 'onFocus',
-        'focus .ckeditor-toolbar-group': 'onFocus'
-      },
-
-      /**
-       * {@inheritdoc}
-       */
-      initialize: function () {
-        // Announce the button and group positions when the model is no longer
-        // dirty.
-        this.listenTo(this.model, 'change:isDirty', this.announceMove);
-      },
-
-      /**
-       * Calls announce on buttons and groups when their position is changed.
-       *
-       * @param Drupal.ckeditor.ConfigurationModel model
-       * @param Boolean isDirty
-       *   A model attribute that indicates if the changed toolbar configuration
-       *   has been stored or not.
-       */
-      announceMove: function (model, isDirty) {
-        // Announce the position of a button or group after the model has been
-        // updated.
-        if (!isDirty) {
-          var item = document.activeElement || null;
-          if (item) {
-            var $item = $(item);
-            if ($item.hasClass('ckeditor-toolbar-group')) {
-              this.announceButtonGroupPosition($item);
-            }
-            else if ($item.parent().hasClass('ckeditor-button')) {
-              this.announceButtonPosition($item.parent());
-            }
-          }
-        }
-      },
-
-      /**
-       * Handles the focus event of elements in the active and available toolbars.
-       *
-       * @param jQuery.Event event
-       */
-      onFocus: function (event) {
-        event.stopPropagation();
-
-        var $originalTarget = $(event.target);
-        var $currentTarget = $(event.currentTarget);
-        var $parent = $currentTarget.parent();
-        if ($parent.hasClass('ckeditor-button') || $parent.hasClass('ckeditor-button-separator')) {
-          this.announceButtonPosition($currentTarget.parent());
-        }
-        else if ($originalTarget.attr('role') !== 'button' && $currentTarget.hasClass('ckeditor-toolbar-group')) {
-          this.announceButtonGroupPosition($currentTarget);
-        }
-      },
-
-      /**
-       * Announces the current position of a button group.
-       *
-       * @param jQuery $group
-       *   A jQuery set that contains an li element that wraps a group of buttons.
-       */
-      announceButtonGroupPosition: function ($group) {
-        var $groups = $group.parent().children();
-        var $row = $group.closest('.ckeditor-row');
-        var $rows = $row.parent().children();
-        var position = $groups.index($group) + 1;
-        var positionCount = $groups.not('.placeholder').length;
-        var row = $rows.index($row) + 1;
-        var rowCount = $rows.not('.placeholder').length;
-        var text = Drupal.t('@groupName button group in position @position of @positionCount in row @row of @rowCount.', {
-          '@groupName': $group.attr('data-drupal-ckeditor-toolbar-group-name'),
-          '@position': position,
-          '@positionCount': positionCount,
-          '@row': row,
-          '@rowCount': rowCount
-        });
-        // If this position is the first in the last row then tell the user that
-        // pressing the down arrow key will create a new row.
-        if (position === 1 && row === rowCount) {
-          text += "\n";
-          text += Drupal.t("Press the down arrow key to create a new row.");
-        }
-        Drupal.announce(text, 'assertive');
-      },
-
-      /**
-       * Announces current button position.
-       *
-       * @param jQuery $button
-       *   A jQuery set that contains an li element that wraps a button.
-       */
-      announceButtonPosition: function ($button) {
-        var $row = $button.closest('.ckeditor-row');
-        var $rows = $row.parent().children();
-        var $buttons = $button.closest('.ckeditor-buttons').children();
-        var $group = $button.closest('.ckeditor-toolbar-group');
-        var $groups = $group.parent().children();
-        var groupPosition = $groups.index($group) + 1;
-        var groupPositionCount = $groups.not('.placeholder').length;
-        var position = $buttons.index($button) + 1;
-        var positionCount = $buttons.length;
-        var row = $rows.index($row) + 1;
-        var rowCount = $rows.not('.placeholder').length;
-        // The name of the button separator is 'button separator' and its type
-        // is 'separator', so we do not want to print the type of this item,
-        // otherwise the UA will speak 'button separator separator'.
-        var type = ($button.attr('data-drupal-ckeditor-type') === 'separator') ? '' : Drupal.t('button');
-        var text;
-        // The button is located in the available button set.
-        if ($button.closest('.ckeditor-toolbar-disabled').length > 0) {
-          text = Drupal.t('@name @type.', {
-            '@name': $button.children().attr('aria-label'),
-            '@type': type
-          });
-          text += "\n" + Drupal.t('Press the down arrow key to activate.');
-
-          Drupal.announce(text, 'assertive');
-        }
-        // The button is in the active toolbar.
-        else if ($group.not('.placeholder').length === 1) {
-          text = Drupal.t('@name @type in position @position of @positionCount in @groupName button group in row @row of @rowCount.', {
-            '@name': $button.children().attr('aria-label'),
-            '@type': type,
-            '@position': position,
-            '@positionCount': positionCount,
-            '@groupName': $group.attr('data-drupal-ckeditor-toolbar-group-name'),
-            '@row': row,
-            '@rowCount': rowCount
-          });
-          // If this position is the first in the last row then tell the user that
-          // pressing the down arrow key will create a new row.
-          if (groupPosition === 1 && position === 1 && row === rowCount) {
-            text += "\n";
-            text += Drupal.t("Press the down arrow key to create a new button group in a new row.");
-          }
-          // If this position is the last one in this row then tell the user that
-          // moving the button to the next group will create a new group.
-          if (groupPosition === groupPositionCount && position === positionCount) {
-            text += "\n";
-            text += Drupal.t("This is the last group. Move the button forward to create a new group.");
-          }
-          Drupal.announce(text, 'assertive');
-        }
-      },
-
-      /**
-       * Provides help information when a button is clicked.
-       *
-       * @param jQuery.Event event
-       */
-      announceButtonHelp: function (event) {
-        var $link = $(event.currentTarget);
-        var $button = $link.parent();
-        var enabled = $button.closest('.ckeditor-toolbar-active').length > 0;
-        var message;
-
-        if (enabled) {
-          message = Drupal.t('The "@name" button is currently enabled.', {
-            '@name': $link.attr('aria-label')
-          });
-          message += "\n" + Drupal.t('Use the keyboard arrow keys to change the position of this button.');
-          message += "\n" + Drupal.t('Press the up arrow key on the top row to disable the button.');
-        }
-        else {
-          message = Drupal.t('The "@name" button is currently disabled.', {
-            '@name': $link.attr('aria-label')
-          });
-          message += "\n" + Drupal.t('Use the down arrow key to move this button into the active toolbar.');
-        }
-        Drupal.announce(message);
-        event.preventDefault();
-      },
-
-      /**
-       * Provides help information when a separator is clicked.
-       *
-       * @param jQuery.Event event
-       */
-      announceSeparatorHelp: function (event) {
-        var $link = $(event.currentTarget);
-        var $button = $link.parent();
-        var enabled = $button.closest('.ckeditor-toolbar-active').length > 0;
-        var message;
-
-        if (enabled) {
-          message = Drupal.t('This @name is currently enabled.', {
-            '@name': $link.attr('aria-label')
-          });
-          message += "\n" + Drupal.t('Use the keyboard arrow keys to change the position of this separator.');
-        }
-        else {
-          message = Drupal.t('Separators are used to visually split individual buttons.');
-          message += "\n" + Drupal.t('This @name is currently disabled.', {
-            '@name': $link.attr('aria-label')
-          });
-          message += "\n" + Drupal.t('Use the down arrow key to move this separator into the active toolbar.');
-          message += "\n" + Drupal.t('You may add multiple separators to each button group.');
-        }
-        Drupal.announce(message);
-        event.preventDefault();
-      }
-    })
-  };
-
-  /**
-   * Translates a change in CKEditor config DOM structure into the config model.
-   *
-   * If the button is moved within an existing group, the DOM structure is simply
-   * translated to a configuration model. If the button is moved into a new group
-   * placeholder, then a process is launched to name that group before the button
-   * move is translated into configuration.
-   *
-   * @param Backbone.View view
-   *   The Backbone View that invoked this function.
-   * @param jQuery $button
-   *   A jQuery set that contains an li element that wraps a button element.
-   * @param function callback
-   *   A callback to invoke after the button group naming modal dialog has been
-   *   closed.
-   */
-  function registerButtonMove(view, $button, callback) {
-    var $group = $button.closest('.ckeditor-toolbar-group');
-
-    // If dropped in a placeholder button group, the user must name it.
-    if ($group.hasClass('placeholder')) {
-
-      if (view.isProcessing) {
-        return;
-      }
-      view.isProcessing = true;
-
-      openGroupNameDialog(view, $group, callback);
-    }
-    else {
-      view.model.set('isDirty', true);
-      callback(true);
-    }
-  }
-
-  /**
-   * Translates a change in CKEditor config DOM structure into the config model.
-   *
-   * Each row has a placeholder group at the end of the row. A user may not move
-   * an existing button group past the placeholder group at the end of a row.
-   *
-   * @param Backbone.View view
-   *   The Backbone View that invoked this function.
-   * @param jQuery $group
-   *   A jQuery set that contains an li element that wraps a group of buttons.
-   */
-  function registerGroupMove(view, $group) {
+    registerGroupMove: function (view, $group) {
     // Remove placeholder classes if necessary.
     var $row = $group.closest('.ckeditor-row');
     if ($row.hasClass('placeholder')) {
@@ -1216,201 +139,204 @@
       }
     });
     view.model.set('isDirty', true);
-  }
-
-  /**
-   * Opens a Drupal dialog with a form for changing the title of a button group.
-   *
-   * @param Backbone.View view
-   *   The Backbone View that invoked this function.
-   * @param jQuery $group
-   *   A jQuery set that contains an li element that wraps a group of buttons.
-   * @param function callback
-   *   A callback to invoke after the button group naming modal dialog has been
-   *   closed.
-   */
-  function openGroupNameDialog(view, $group, callback) {
-    callback = callback || function () {};
+  },
 
     /**
-     * Validates the string provided as a button group title.
+     * Opens a Drupal dialog with a form for changing the title of a button group.
      *
-     * @param DOM form
-     *   The form DOM element that contains the input with the new button group
-     *   title string.
-     * @return Boolean
-     *   Returns true when an error exists, otherwise returns false.
+     * @param Backbone.View view
+     *   The Backbone View that invoked this function.
+     * @param jQuery $group
+     *   A jQuery set that contains an li element that wraps a group of buttons.
+     * @param function callback
+     *   A callback to invoke after the button group naming modal dialog has been
+     *   closed.
      */
-    function validateForm(form) {
-      if (form.elements[0].value.length === 0) {
-        var $form = $(form);
-        if (!$form.hasClass('errors')) {
-          $form
-            .addClass('errors')
-            .find('input')
-            .addClass('error')
-            .attr('aria-invalid', 'true');
-          $('<div class=\"description\" >' + Drupal.t('Please provide a name for the button group.') + '</div>').insertAfter(form.elements[0]);
-        }
-        return true;
-      }
-      return false;
-    }
-
-    /**
-     * Attempts to close the dialog; Validates user input.
-     *
-     * @param String action
-     *   The dialog action chosen by the user: 'apply' or 'cancel'.
-     * @param DOM form
-     *   The form DOM element that contains the input with the new button group
-     *   title string.
-     */
-    function closeDialog(action, form) {
+    openGroupNameDialog: function (view, $group, callback) {
+      callback = callback || function () {};
 
       /**
-       * Closes the dialog when the user cancels or supplies valid data.
-       */
-      function shutdown() {
-        dialog.close(action);
-
-        // The processing marker can be deleted since the dialog has been closed.
-        delete view.isProcessing;
+       * Validates the string provided as a button group title.
+       *
+       * @param DOM form
+       *   The form DOM element that contains the input with the new button group
+       *   title string.
+       * @return Boolean
+       *   Returns true when an error exists, otherwise returns false.
+       */
+      function validateForm(form) {
+        if (form.elements[0].value.length === 0) {
+          var $form = $(form);
+          if (!$form.hasClass('errors')) {
+            $form
+              .addClass('errors')
+              .find('input')
+              .addClass('error')
+              .attr('aria-invalid', 'true');
+            $('<div class=\"description\" >' + Drupal.t('Please provide a name for the button group.') + '</div>').insertAfter(form.elements[0]);
+          }
+          return true;
+        }
+        return false;
       }
 
       /**
-       * Applies a string as the name of a CKEditor button group.
+       * Attempts to close the dialog; Validates user input.
        *
-       * @param jQuery $group
-       *   A jQuery set that contains an li element that wraps a group of buttons.
-       * @param String name
-       *   The new name of the CKEditor button group.
+       * @param String action
+       *   The dialog action chosen by the user: 'apply' or 'cancel'.
+       * @param DOM form
+       *   The form DOM element that contains the input with the new button group
+       *   title string.
        */
-      function namePlaceholderGroup($group, name) {
-        // If it's currently still a placeholder, then that means we're creating
-        // a new group, and we must do some extra work.
-        if ($group.hasClass('placeholder')) {
-          // Remove all whitespace from the name, lowercase it and ensure
-          // HTML-safe encoding, then use this as the group ID for CKEditor
-          // configuration UI accessibility purposes only.
-          var groupID = 'ckeditor-toolbar-group-aria-label-for-' + Drupal.checkPlain(name.toLowerCase().replace(/\s/g, '-'));
+      function closeDialog(action, form) {
+
+        /**
+         * Closes the dialog when the user cancels or supplies valid data.
+         */
+        function shutdown() {
+          dialog.close(action);
+
+          // The processing marker can be deleted since the dialog has been closed.
+          delete view.isProcessing;
+        }
+
+        /**
+         * Applies a string as the name of a CKEditor button group.
+         *
+         * @param jQuery $group
+         *   A jQuery set that contains an li element that wraps a group of buttons.
+         * @param String name
+         *   The new name of the CKEditor button group.
+         */
+        function namePlaceholderGroup($group, name) {
+          // If it's currently still a placeholder, then that means we're creating
+          // a new group, and we must do some extra work.
+          if ($group.hasClass('placeholder')) {
+            // Remove all whitespace from the name, lowercase it and ensure
+            // HTML-safe encoding, then use this as the group ID for CKEditor
+            // configuration UI accessibility purposes only.
+            var groupID = 'ckeditor-toolbar-group-aria-label-for-' + Drupal.checkPlain(name.toLowerCase().replace(/\s/g, '-'));
+            $group
+              // Update the group container.
+              .removeAttr('aria-label')
+              .attr('data-drupal-ckeditor-type', 'group')
+              .attr('tabindex', 0)
+              // Update the group heading.
+              .children('.ckeditor-toolbar-group-name')
+              .attr('id', groupID)
+              .end()
+              // Update the group items.
+              .children('.ckeditor-toolbar-group-buttons')
+              .attr('aria-labelledby', groupID);
+          }
+
           $group
-            // Update the group container.
-            .removeAttr('aria-label')
-            .attr('data-drupal-ckeditor-type', 'group')
-            .attr('tabindex', 0)
-            // Update the group heading.
+            .attr('data-drupal-ckeditor-toolbar-group-name', name)
             .children('.ckeditor-toolbar-group-name')
-            .attr('id', groupID)
-            .end()
-            // Update the group items.
-            .children('.ckeditor-toolbar-group-buttons')
-            .attr('aria-labelledby', groupID);
+            .text(name);
         }
 
-        $group
-          .attr('data-drupal-ckeditor-toolbar-group-name', name)
-          .children('.ckeditor-toolbar-group-name')
-          .text(name);
-      }
-
-      // Invoke a user-provided callback and indicate failure.
-      if (action === 'cancel') {
-        shutdown();
-        callback(false, $group);
-        return;
-      }
+        // Invoke a user-provided callback and indicate failure.
+        if (action === 'cancel') {
+          shutdown();
+          callback(false, $group);
+          return;
+        }
 
-      // Validate that a group name was provided.
-      if (form && validateForm(form)) {
-        return;
-      }
+        // Validate that a group name was provided.
+        if (form && validateForm(form)) {
+          return;
+        }
 
-      // React to application of a valid group name.
-      if (action === 'apply') {
-        shutdown();
-        // Apply the provided name to the button group label.
-        namePlaceholderGroup($group, Drupal.checkPlain(form.elements[0].value));
-        // Remove placeholder classes so that new placeholders will be
-        // inserted.
-        $group.closest('.ckeditor-row.placeholder').addBack().removeClass('placeholder');
+        // React to application of a valid group name.
+        if (action === 'apply') {
+          shutdown();
+          // Apply the provided name to the button group label.
+          namePlaceholderGroup($group, Drupal.checkPlain(form.elements[0].value));
+          // Remove placeholder classes so that new placeholders will be
+          // inserted.
+          $group.closest('.ckeditor-row.placeholder').addBack().removeClass('placeholder');
 
-        // Invoke a user-provided callback and indicate success.
-        callback(true, $group);
+          // Invoke a user-provided callback and indicate success.
+          callback(true, $group);
 
-        // Signal that the active toolbar DOM structure has changed.
-        view.model.set('isDirty', true);
+          // Signal that the active toolbar DOM structure has changed.
+          view.model.set('isDirty', true);
+        }
       }
-    }
 
-    // Create a Drupal dialog that will get a button group name from the user.
-    var $ckeditorButtonGroupNameForm = $(Drupal.theme('ckeditorButtonGroupNameForm'));
-    var dialog = Drupal.dialog($ckeditorButtonGroupNameForm.get(0), {
-      title: Drupal.t('Button group name'),
-      dialogClass: 'ckeditor-name-toolbar-group',
-      resizable: false,
-      buttons: [
-        {
-          text: Drupal.t('Apply'),
-          click: function () {
-            closeDialog('apply', this);
+      // Create a Drupal dialog that will get a button group name from the user.
+      var $ckeditorButtonGroupNameForm = $(Drupal.theme('ckeditorButtonGroupNameForm'));
+      var dialog = Drupal.dialog($ckeditorButtonGroupNameForm.get(0), {
+        title: Drupal.t('Button group name'),
+        dialogClass: 'ckeditor-name-toolbar-group',
+        resizable: false,
+        buttons: [
+          {
+            text: Drupal.t('Apply'),
+            click: function () {
+              closeDialog('apply', this);
+            },
+            primary: true
           },
-          primary: true
-        },
-        {
-          text: Drupal.t('Cancel'),
-          click: function () {
-            closeDialog('cancel');
-          }
-        }
-      ],
-      open: function () {
-        var form = this;
-        var $form = $(this);
-        var $widget = $form.parent();
-        $widget.find('.ui-dialog-titlebar-close').remove();
-        // Set a click handler on the input and button in the form.
-        $widget.on('keypress.ckeditor', 'input, button', function (event) {
-          // React to enter key press.
-          if (event.keyCode === 13) {
-            var $target = $(event.currentTarget);
-            var data = $target.data('ui-button');
-            var action = 'apply';
-            // Assume 'apply', but take into account that the user might have
-            // pressed the enter key on the dialog buttons.
-            if (data && data.options && data.options.label) {
-              action = data.options.label.toLowerCase();
+          {
+            text: Drupal.t('Cancel'),
+            click: function () {
+              closeDialog('cancel');
             }
-            closeDialog(action, form);
-            event.stopPropagation();
-            event.stopImmediatePropagation();
-            event.preventDefault();
           }
-        });
-        // Announce to the user that a modal dialog is open.
-        var text = Drupal.t('Editing the name of the new button group in a dialog.');
-        if ($group.attr('data-drupal-ckeditor-toolbar-group-name') !== undefined) {
-          text = Drupal.t('Editing the name of the "@groupName" button group in a dialog.', {
-            '@groupName': $group.attr('data-drupal-ckeditor-toolbar-group-name')
+        ],
+        open: function () {
+          var form = this;
+          var $form = $(this);
+          var $widget = $form.parent();
+          $widget.find('.ui-dialog-titlebar-close').remove();
+          // Set a click handler on the input and button in the form.
+          $widget.on('keypress.ckeditor', 'input, button', function (event) {
+            // React to enter key press.
+            if (event.keyCode === 13) {
+              var $target = $(event.currentTarget);
+              var data = $target.data('ui-button');
+              var action = 'apply';
+              // Assume 'apply', but take into account that the user might have
+              // pressed the enter key on the dialog buttons.
+              if (data && data.options && data.options.label) {
+                action = data.options.label.toLowerCase();
+              }
+              closeDialog(action, form);
+              event.stopPropagation();
+              event.stopImmediatePropagation();
+              event.preventDefault();
+            }
           });
+          // Announce to the user that a modal dialog is open.
+          var text = Drupal.t('Editing the name of the new button group in a dialog.');
+          if ($group.attr('data-drupal-ckeditor-toolbar-group-name') !== undefined) {
+            text = Drupal.t('Editing the name of the "@groupName" button group in a dialog.', {
+              '@groupName': $group.attr('data-drupal-ckeditor-toolbar-group-name')
+            });
+          }
+          Drupal.announce(text);
+        },
+        close: function (event) {
+          // Automatically destroy the DOM element that was used for the dialog.
+          $(event.target).remove();
         }
-        Drupal.announce(text);
-      },
-      close: function (event) {
-        // Automatically destroy the DOM element that was used for the dialog.
-        $(event.target).remove();
-      }
-    });
-    // A modal dialog is used because the user must provide a button group name
-    // or cancel the button placement before taking any other action.
-    dialog.showModal();
+      });
+      // A modal dialog is used because the user must provide a button group name
+      // or cancel the button placement before taking any other action.
+      dialog.showModal();
+
+      $(document.querySelector('.ckeditor-name-toolbar-group').querySelector('input'))
+        // When editing, set the "group name" input in the form to the current value.
+        .attr('value', $group.attr('data-drupal-ckeditor-toolbar-group-name'))
+        // Focus on the "group name" input in the form.
+        .trigger('focus');
+    }
+
+  };
 
-    $(document.querySelector('.ckeditor-name-toolbar-group').querySelector('input'))
-      // When editing, set the "group name" input in the form to the current value.
-      .attr('value', $group.attr('data-drupal-ckeditor-toolbar-group-name'))
-      // Focus on the "group name" input in the form.
-      .trigger('focus');
-  }
 
   /**
    * Automatically shows/hides settings of buttons-only CKEditor plugins.
diff --git a/core/modules/ckeditor/js/models/Model.js b/core/modules/ckeditor/js/models/Model.js
new file mode 100644
index 0000000..1d26719
--- /dev/null
+++ b/core/modules/ckeditor/js/models/Model.js
@@ -0,0 +1,38 @@
+/**
+ * @file
+ * A Backbone Model for the state of a CKEditor toolbar configuration .
+ */
+
+(function (Drupal, Backbone) {
+
+    "use strict";
+
+    /**
+     * Backbone model for the CKEditor toolbar configuration state.
+     */
+    Drupal.ckeditor.Model = Backbone.Model.extend({
+        defaults: {
+            // The CKEditor configuration that is being manipulated through the UI.
+            activeEditorConfig: null,
+            // The textarea that contains the serialized representation of the active
+            // CKEditor configuration.
+            $textarea: null,
+            // Tracks whether the active toolbar DOM structure has been changed. When
+            // true, activeEditorConfig needs to be updated, and when that is updated,
+            // $textarea will also be updated.
+            isDirty: false,
+            // The configuration for the hidden CKEditor instance that is used to build
+            // the features metadata.
+            hiddenEditorConfig: null,
+            // A hash, keyed by a feature name, that details CKEditor plugin features.
+            featuresMetadata: null,
+            // Whether the button group names are currently visible.
+            groupNamesVisible: false
+        },
+        sync: function () {
+            // Push the settings into the textarea.
+            this.get('$textarea').val(JSON.stringify(this.get('activeEditorConfig')));
+        }
+    });
+
+})(Drupal, Backbone);
\ No newline at end of file
diff --git a/core/modules/ckeditor/js/views/AuralView.js b/core/modules/ckeditor/js/views/AuralView.js
new file mode 100644
index 0000000..794a1b2
--- /dev/null
+++ b/core/modules/ckeditor/js/views/AuralView.js
@@ -0,0 +1,224 @@
+/**
+ * @file
+ * A Backbone View that provides the aural view of CKEditor toolbar configuration.
+ */
+
+(function (Drupal, Backbone, $) {
+
+  "use strict";
+
+    /**
+     * Backbone View for CKEditor toolbar configuration; aural UX (output only).
+     */
+    Drupal.ckeditor.AuralView = Backbone.View.extend({
+
+        events: {
+            'click .ckeditor-buttons a': 'announceButtonHelp',
+            'click .ckeditor-multiple-buttons a': 'announceSeparatorHelp',
+            'focus .ckeditor-button a': 'onFocus',
+            'focus .ckeditor-button-separator a': 'onFocus',
+            'focus .ckeditor-toolbar-group': 'onFocus'
+        },
+
+        /**
+         * {@inheritdoc}
+         */
+        initialize: function () {
+            // Announce the button and group positions when the model is no longer
+            // dirty.
+            this.listenTo(this.model, 'change:isDirty', this.announceMove);
+        },
+
+        /**
+         * Calls announce on buttons and groups when their position is changed.
+         *
+         * @param Drupal.ckeditor.ConfigurationModel model
+         * @param Boolean isDirty
+         *   A model attribute that indicates if the changed toolbar configuration
+         *   has been stored or not.
+         */
+        announceMove: function (model, isDirty) {
+            // Announce the position of a button or group after the model has been
+            // updated.
+            if (!isDirty) {
+                var item = document.activeElement || null;
+                if (item) {
+                    var $item = $(item);
+                    if ($item.hasClass('ckeditor-toolbar-group')) {
+                        this.announceButtonGroupPosition($item);
+                    }
+                    else if ($item.parent().hasClass('ckeditor-button')) {
+                        this.announceButtonPosition($item.parent());
+                    }
+                }
+            }
+        },
+
+        /**
+         * Handles the focus event of elements in the active and available toolbars.
+         *
+         * @param jQuery.Event event
+         */
+        onFocus: function (event) {
+            event.stopPropagation();
+
+            var $originalTarget = $(event.target);
+            var $currentTarget = $(event.currentTarget);
+            var $parent = $currentTarget.parent();
+            if ($parent.hasClass('ckeditor-button') || $parent.hasClass('ckeditor-button-separator')) {
+                this.announceButtonPosition($currentTarget.parent());
+            }
+            else if ($originalTarget.attr('role') !== 'button' && $currentTarget.hasClass('ckeditor-toolbar-group')) {
+                this.announceButtonGroupPosition($currentTarget);
+            }
+        },
+
+        /**
+         * Announces the current position of a button group.
+         *
+         * @param jQuery $group
+         *   A jQuery set that contains an li element that wraps a group of buttons.
+         */
+        announceButtonGroupPosition: function ($group) {
+            var $groups = $group.parent().children();
+            var $row = $group.closest('.ckeditor-row');
+            var $rows = $row.parent().children();
+            var position = $groups.index($group) + 1;
+            var positionCount = $groups.not('.placeholder').length;
+            var row = $rows.index($row) + 1;
+            var rowCount = $rows.not('.placeholder').length;
+            var text = Drupal.t('@groupName button group in position @position of @positionCount in row @row of @rowCount.', {
+                '@groupName': $group.attr('data-drupal-ckeditor-toolbar-group-name'),
+                '@position': position,
+                '@positionCount': positionCount,
+                '@row': row,
+                '@rowCount': rowCount
+            });
+            // If this position is the first in the last row then tell the user that
+            // pressing the down arrow key will create a new row.
+            if (position === 1 && row === rowCount) {
+                text += "\n";
+                text += Drupal.t("Press the down arrow key to create a new row.");
+            }
+            Drupal.announce(text, 'assertive');
+        },
+
+        /**
+         * Announces current button position.
+         *
+         * @param jQuery $button
+         *   A jQuery set that contains an li element that wraps a button.
+         */
+        announceButtonPosition: function ($button) {
+            var $row = $button.closest('.ckeditor-row');
+            var $rows = $row.parent().children();
+            var $buttons = $button.closest('.ckeditor-buttons').children();
+            var $group = $button.closest('.ckeditor-toolbar-group');
+            var $groups = $group.parent().children();
+            var groupPosition = $groups.index($group) + 1;
+            var groupPositionCount = $groups.not('.placeholder').length;
+            var position = $buttons.index($button) + 1;
+            var positionCount = $buttons.length;
+            var row = $rows.index($row) + 1;
+            var rowCount = $rows.not('.placeholder').length;
+            // The name of the button separator is 'button separator' and its type
+            // is 'separator', so we do not want to print the type of this item,
+            // otherwise the UA will speak 'button separator separator'.
+            var type = ($button.attr('data-drupal-ckeditor-type') === 'separator') ? '' : Drupal.t('button');
+            var text;
+            // The button is located in the available button set.
+            if ($button.closest('.ckeditor-toolbar-disabled').length > 0) {
+                text = Drupal.t('@name @type.', {
+                    '@name': $button.children().attr('aria-label'),
+                    '@type': type
+                });
+                text += "\n" + Drupal.t('Press the down arrow key to activate.');
+
+                Drupal.announce(text, 'assertive');
+            }
+            // The button is in the active toolbar.
+            else if ($group.not('.placeholder').length === 1) {
+                text = Drupal.t('@name @type in position @position of @positionCount in @groupName button group in row @row of @rowCount.', {
+                    '@name': $button.children().attr('aria-label'),
+                    '@type': type,
+                    '@position': position,
+                    '@positionCount': positionCount,
+                    '@groupName': $group.attr('data-drupal-ckeditor-toolbar-group-name'),
+                    '@row': row,
+                    '@rowCount': rowCount
+                });
+                // If this position is the first in the last row then tell the user that
+                // pressing the down arrow key will create a new row.
+                if (groupPosition === 1 && position === 1 && row === rowCount) {
+                    text += "\n";
+                    text += Drupal.t("Press the down arrow key to create a new button group in a new row.");
+                }
+                // If this position is the last one in this row then tell the user that
+                // moving the button to the next group will create a new group.
+                if (groupPosition === groupPositionCount && position === positionCount) {
+                    text += "\n";
+                    text += Drupal.t("This is the last group. Move the button forward to create a new group.");
+                }
+                Drupal.announce(text, 'assertive');
+            }
+        },
+
+        /**
+         * Provides help information when a button is clicked.
+         *
+         * @param jQuery.Event event
+         */
+        announceButtonHelp: function (event) {
+            var $link = $(event.currentTarget);
+            var $button = $link.parent();
+            var enabled = $button.closest('.ckeditor-toolbar-active').length > 0;
+            var message;
+
+            if (enabled) {
+                message = Drupal.t('The "@name" button is currently enabled.', {
+                    '@name': $link.attr('aria-label')
+                });
+                message += "\n" + Drupal.t('Use the keyboard arrow keys to change the position of this button.');
+                message += "\n" + Drupal.t('Press the up arrow key on the top row to disable the button.');
+            }
+            else {
+                message = Drupal.t('The "@name" button is currently disabled.', {
+                    '@name': $link.attr('aria-label')
+                });
+                message += "\n" + Drupal.t('Use the down arrow key to move this button into the active toolbar.');
+            }
+            Drupal.announce(message);
+            event.preventDefault();
+        },
+
+        /**
+         * Provides help information when a separator is clicked.
+         *
+         * @param jQuery.Event event
+         */
+        announceSeparatorHelp: function (event) {
+            var $link = $(event.currentTarget);
+            var $button = $link.parent();
+            var enabled = $button.closest('.ckeditor-toolbar-active').length > 0;
+            var message;
+
+            if (enabled) {
+                message = Drupal.t('This @name is currently enabled.', {
+                    '@name': $link.attr('aria-label')
+                });
+                message += "\n" + Drupal.t('Use the keyboard arrow keys to change the position of this separator.');
+            }
+            else {
+                message = Drupal.t('Separators are used to visually split individual buttons.');
+                message += "\n" + Drupal.t('This @name is currently disabled.', {
+                    '@name': $link.attr('aria-label')
+                });
+                message += "\n" + Drupal.t('Use the down arrow key to move this separator into the active toolbar.');
+                message += "\n" + Drupal.t('You may add multiple separators to each button group.');
+            }
+            Drupal.announce(message);
+            event.preventDefault();
+        }
+    });
+
+})(Drupal, Backbone, jQuery);
diff --git a/core/modules/ckeditor/js/views/ControllerView.js b/core/modules/ckeditor/js/views/ControllerView.js
new file mode 100644
index 0000000..ed701a5
--- /dev/null
+++ b/core/modules/ckeditor/js/views/ControllerView.js
@@ -0,0 +1,354 @@
+/**
+ * @file
+ * A Backbone View acting as a controller for CKEditor toolbar configuration.
+ */
+
+(function (Drupal, Backbone, $) {
+
+    "use strict";
+
+    /**
+     * Backbone View acting as a controller for CKEditor toolbar configuration.
+     */
+    Drupal.ckeditor.ControllerView = Backbone.View.extend({
+
+        events: {},
+
+        /**
+         * {@inheritdoc}
+         */
+        initialize: function () {
+            this.getCKEditorFeatures(this.model.get('hiddenEditorConfig'), this.disableFeaturesDisallowedByFilters.bind(this));
+
+            // Push the active editor configuration to the textarea.
+            this.model.listenTo(this.model, 'change:activeEditorConfig', this.model.sync);
+            this.listenTo(this.model, 'change:isDirty', this.parseEditorDOM);
+        },
+
+        /**
+         * Converts the active toolbar DOM structure to an object representation.
+         *
+         * @param Drupal.ckeditor.ConfigurationModel model
+         *   The state model for the CKEditor configuration.
+         * @param Boolean isDirty
+         *   Tracks whether the active toolbar DOM structure has been changed.
+         *   isDirty is toggled back to false in this method.
+         * @param Object options
+         *   An object that includes:
+         *   - Boolean broadcast: (optional) A flag that controls whether a
+         *     CKEditorToolbarChanged event should be fired for configuration
+         *     changes.
+         */
+        parseEditorDOM: function (model, isDirty, options) {
+            if (isDirty) {
+                var currentConfig = this.model.get('activeEditorConfig');
+
+                // Process the rows.
+                var rows = [];
+                this.$el
+                    .find('.ckeditor-active-toolbar-configuration')
+                    .children('.ckeditor-row').each(function () {
+                        var groups = [];
+                        // Process the button groups.
+                        $(this).find('.ckeditor-toolbar-group').each(function () {
+                            var $group = $(this);
+                            var $buttons = $group.find('.ckeditor-button');
+                            if ($buttons.length) {
+                                var group = {
+                                    name: $group.attr('data-drupal-ckeditor-toolbar-group-name'),
+                                    items: []
+                                };
+                                $group.find('.ckeditor-button, .ckeditor-multiple-button').each(function () {
+                                    group.items.push($(this).attr('data-drupal-ckeditor-button-name'));
+                                });
+                                groups.push(group);
+                            }
+                        });
+                        if (groups.length) {
+                            rows.push(groups);
+                        }
+                    });
+                this.model.set('activeEditorConfig', rows);
+                // Mark the model as clean. Whether or not the sync to the textfield
+                // occurs depends on the activeEditorConfig attribute firing a change
+                // event. The DOM has at least been processed and posted, so as far as
+                // the model is concerned, it is clean.
+                this.model.set('isDirty', false);
+
+                // Determine whether we should trigger an event.
+                if (options.broadcast !== false) {
+                    var prev = this.getButtonList(currentConfig);
+                    var next = this.getButtonList(rows);
+                    if (prev.length !== next.length) {
+                        this.$el
+                            .find('.ckeditor-toolbar-active')
+                            .trigger('CKEditorToolbarChanged', [
+                                (prev.length < next.length) ? 'added' : 'removed',
+                                _.difference(_.union(prev, next), _.intersection(prev, next))[0]
+                            ]);
+                    }
+                }
+            }
+        },
+
+        /**
+         * Asynchronously retrieve the metadata for all available CKEditor features.
+         *
+         * In order to get a list of all features needed by CKEditor, we create a
+         * hidden CKEditor instance, then check the CKEditor's "allowedContent"
+         * filter settings. Because creating an instance is expensive, a callback
+         * must be provided that will receive a hash of Drupal.EditorFeature
+         * features keyed by feature (button) name.
+         *
+         * @param Object CKEditorConfig
+         *   An object that represents the configuration settings for a CKEditor
+         *   editor component.
+         * @param Function callback
+         *   A function to invoke when the instanceReady event is fired by the
+         *   CKEditor object.
+         */
+        getCKEditorFeatures: function (CKEditorConfig, callback) {
+            var getProperties = function (CKEPropertiesList) {
+                return (_.isObject(CKEPropertiesList)) ? _.keys(CKEPropertiesList) : [];
+            };
+
+            var convertCKERulesToEditorFeature = function (feature, CKEFeatureRules) {
+                for (var i = 0; i < CKEFeatureRules.length; i++) {
+                    var CKERule = CKEFeatureRules[i];
+                    var rule = new Drupal.EditorFeatureHTMLRule();
+
+                    // Tags.
+                    var tags = getProperties(CKERule.elements);
+                    rule.required.tags = (CKERule.propertiesOnly) ? [] : tags;
+                    rule.allowed.tags = tags;
+                    // Attributes.
+                    rule.required.attributes = getProperties(CKERule.requiredAttributes);
+                    rule.allowed.attributes = getProperties(CKERule.attributes);
+                    // Styles.
+                    rule.required.styles = getProperties(CKERule.requiredStyles);
+                    rule.allowed.styles = getProperties(CKERule.styles);
+                    // Classes.
+                    rule.required.classes = getProperties(CKERule.requiredClasses);
+                    rule.allowed.classes = getProperties(CKERule.classes);
+                    // Raw.
+                    rule.raw = CKERule;
+
+                    feature.addHTMLRule(rule);
+                }
+            };
+
+            // Create hidden CKEditor with all features enabled, retrieve metadata.
+            // @see \Drupal\ckeditor\Plugin\Editor\CKEditor::settingsForm.
+            var hiddenCKEditorID = 'ckeditor-hidden';
+            if (CKEDITOR.instances[hiddenCKEditorID]) {
+                CKEDITOR.instances[hiddenCKEditorID].destroy(true);
+            }
+            // Load external plugins, if any.
+            var hiddenEditorConfig = this.model.get('hiddenEditorConfig');
+            if (hiddenEditorConfig.drupalExternalPlugins) {
+                var externalPlugins = hiddenEditorConfig.drupalExternalPlugins;
+                for (var pluginName in externalPlugins) {
+                    if (externalPlugins.hasOwnProperty(pluginName)) {
+                        CKEDITOR.plugins.addExternal(pluginName, externalPlugins[pluginName], '');
+                    }
+                }
+            }
+            CKEDITOR.inline($('#' + hiddenCKEditorID).get(0), CKEditorConfig);
+
+            // Once the instance is ready, retrieve the allowedContent filter rules
+            // and convert them to Drupal.EditorFeature objects.
+            CKEDITOR.once('instanceReady', function (e) {
+                if (e.editor.name === hiddenCKEditorID) {
+                    // First collect all CKEditor allowedContent rules.
+                    var CKEFeatureRulesMap = {};
+                    var rules = e.editor.filter.allowedContent;
+                    var rule, name;
+                    for (var i = 0; i < rules.length; i++) {
+                        rule = rules[i];
+                        name = rule.featureName || ':(';
+                        if (!CKEFeatureRulesMap[name]) {
+                            CKEFeatureRulesMap[name] = [];
+                        }
+                        CKEFeatureRulesMap[name].push(rule);
+                    }
+
+                    // Now convert these to Drupal.EditorFeature objects.
+                    var features = {};
+                    for (var featureName in CKEFeatureRulesMap) {
+                        if (CKEFeatureRulesMap.hasOwnProperty(featureName)) {
+                            var feature = new Drupal.EditorFeature(featureName);
+                            convertCKERulesToEditorFeature(feature, CKEFeatureRulesMap[featureName]);
+                            features[featureName] = feature;
+                        }
+                    }
+
+                    callback(features);
+                }
+            });
+        },
+
+        /**
+         * Retrieves the feature for a given button from featuresMetadata. Returns
+         * false if the given button is in fact a divider.
+         *
+         * @param String button
+         *   The name of a CKEditor button.
+         * @return Object
+         *   The feature metadata object for a button.
+         */
+        getFeatureForButton: function (button) {
+            // Return false if the button being added is a divider.
+            if (button === '-') {
+                return false;
+            }
+
+            // Get a Drupal.editorFeature object that contains all metadata for
+            // the feature that was just added or removed. Not every feature has
+            // such metadata.
+            var featureName = button.toLowerCase();
+            var featuresMetadata = this.model.get('featuresMetadata');
+            if (!featuresMetadata[featureName]) {
+                featuresMetadata[featureName] = new Drupal.EditorFeature(featureName);
+                this.model.set('featuresMetadata', featuresMetadata);
+            }
+            return featuresMetadata[featureName];
+        },
+
+        /**
+         * Checks buttons against filter settings; disables disallowed buttons.
+         *
+         * @param Object features
+         *   A map of Drupal.EditorFeature objects.
+         */
+        disableFeaturesDisallowedByFilters: function (features) {
+            this.model.set('featuresMetadata', features);
+
+            // Ensure that toolbar configuration changes are broadcast.
+            this.broadcastConfigurationChanges(this.$el);
+
+            // Initialization: not all of the default toolbar buttons may be allowed
+            // by the current filter settings. Remove any of the default toolbar
+            // buttons that require more permissive filter settings. The remaining
+            // default toolbar buttons are marked as "added".
+            var existingButtons = [];
+            // Loop through each button group after flattening the groups from the
+            // toolbar row arrays.
+            for (var i = 0, buttonGroups = _.flatten(this.model.get('activeEditorConfig')); i < buttonGroups.length; i++) {
+                // Pull the button names from each toolbar button group.
+                for (var k = 0, buttons = buttonGroups[i].items; k < buttons.length; k++) {
+                    existingButtons.push(buttons[k]);
+                }
+            }
+            // Remove duplicate buttons.
+            existingButtons = _.unique(existingButtons);
+            // Prepare the active toolbar and available-button toolbars.
+            for (i = 0; i < existingButtons.length; i++) {
+                var button = existingButtons[i];
+                var feature = this.getFeatureForButton(button);
+                // Skip dividers.
+                if (feature === false) {
+                    continue;
+                }
+
+                if (Drupal.editorConfiguration.featureIsAllowedByFilters(feature)) {
+                    // Existing toolbar buttons are in fact "added features".
+                    this.$el.find('.ckeditor-toolbar-active').trigger('CKEditorToolbarChanged', ['added', existingButtons[i]]);
+                }
+                else {
+                    // Move the button element from the active the active toolbar to the
+                    // list of available buttons.
+                    $('.ckeditor-toolbar-active li[data-drupal-ckeditor-button-name="' + button + '"]')
+                        .detach()
+                        .appendTo('.ckeditor-toolbar-disabled > .ckeditor-toolbar-available > ul');
+                    // Update the toolbar value field.
+                    this.model.set({'isDirty': true}, {broadcast: false});
+                }
+            }
+        },
+
+        /**
+         * Sets up broadcasting of CKEditor toolbar configuration changes.
+         *
+         * @param jQuery $ckeditorToolbar
+         *   The active toolbar DOM element wrapped in jQuery.
+         */
+        broadcastConfigurationChanges: function ($ckeditorToolbar) {
+            var view = this;
+            var hiddenEditorConfig = this.model.get('hiddenEditorConfig');
+            var featuresMetadata = this.model.get('featuresMetadata');
+            var getFeatureForButton = this.getFeatureForButton.bind(this);
+            var getCKEditorFeatures = this.getCKEditorFeatures.bind(this);
+            $ckeditorToolbar
+                .find('.ckeditor-toolbar-active')
+                // Listen for CKEditor toolbar configuration changes. When a button is
+                // added/removed, call an appropriate Drupal.editorConfiguration method.
+                .on('CKEditorToolbarChanged.ckeditorAdmin', function (event, action, button) {
+                    var feature = getFeatureForButton(button);
+
+                    // Early-return if the button being added is a divider.
+                    if (feature === false) {
+                        return;
+                    }
+
+                    // Trigger a standardized text editor configuration event to indicate
+                    // whether a feature was added or removed, so that filters can react.
+                    var configEvent = (action === 'added') ? 'addedFeature' : 'removedFeature';
+                    Drupal.editorConfiguration[configEvent](feature);
+                })
+                // Listen for CKEditor plugin settings changes. When a plugin setting is
+                // changed, rebuild the CKEditor features metadata.
+                .on('CKEditorPluginSettingsChanged.ckeditorAdmin', function (event, settingsChanges) {
+                    // Update hidden CKEditor configuration.
+                    for (var key in settingsChanges) {
+                        if (settingsChanges.hasOwnProperty(key)) {
+                            hiddenEditorConfig[key] = settingsChanges[key];
+                        }
+                    }
+
+                    // Retrieve features for the updated hidden CKEditor configuration.
+                    getCKEditorFeatures(hiddenEditorConfig, function (features) {
+                        // Trigger a standardized text editor configuration event for each
+                        // feature that was modified by the configuration changes.
+                        for (var name in features) {
+                            if (features.hasOwnProperty(name)) {
+                                var feature = features[name];
+                                if (featuresMetadata.hasOwnProperty(name) && !_.isEqual(featuresMetadata[name], feature)) {
+                                    Drupal.editorConfiguration.modifiedFeature(feature);
+                                }
+                            }
+                        }
+                        // Update the CKEditor features metadata.
+                        view.model.set('featuresMetadata', features);
+                    });
+                });
+        },
+
+        /**
+         * Returns the list of buttons from an editor configuration.
+         *
+         * @param Object config
+         *   A CKEditor configuration object.
+         * @return Array
+         *   A list of buttons in the CKEditor configuration.
+         */
+        getButtonList: function (config) {
+            var buttons = [];
+            // Remove the rows
+            config = _.flatten(config);
+
+            // Loop through the button groups and pull out the buttons.
+            config.forEach(function (group) {
+                group.items.forEach(function (button) {
+                    buttons.push(button);
+                });
+            });
+
+            // Remove the dividing elements if any.
+            return _.without(buttons, '-');
+        }
+    });
+
+})(Drupal, Backbone, jQuery);
+
+
+
diff --git a/core/modules/ckeditor/js/views/KeyboardView.js b/core/modules/ckeditor/js/views/KeyboardView.js
new file mode 100644
index 0000000..0edf712
--- /dev/null
+++ b/core/modules/ckeditor/js/views/KeyboardView.js
@@ -0,0 +1,260 @@
+/**
+ * @file
+ * A Backbone View that provides the aural view of CKEditor keyboard UX configuration.
+ */
+
+(function (Drupal, Backbone, $) {
+
+    "use strict";
+
+    /**
+     * Backbone View for CKEditor toolbar configuration; keyboard UX.
+     */
+    Drupal.ckeditor.KeyboardView = Backbone.View.extend({
+
+        /**
+         * {@inheritdoc}
+         */
+        initialize: function () {
+            // Add keyboard arrow support.
+            this.$el.on('keydown.ckeditor', '.ckeditor-buttons a, .ckeditor-multiple-buttons a', this.onPressButton.bind(this));
+            this.$el.on('keydown.ckeditor', '[data-drupal-ckeditor-type="group"]', this.onPressGroup.bind(this));
+        },
+
+        /**
+         * {@inheritdoc}
+         */
+        render: function () {},
+
+        /**
+         * Handles keypresses on a CKEditor configuration button.
+         *
+         * @param jQuery.Event event
+         */
+        onPressButton: function (event) {
+            var upDownKeys = [
+                38, // Up arrow.
+                63232, // Safari up arrow.
+                40, // Down arrow.
+                63233 // Safari down arrow.
+            ];
+            var leftRightKeys = [
+                37, // Left arrow.
+                63234, // Safari left arrow.
+                39, // Right arrow.
+                63235 // Safari right arrow.
+            ];
+
+            // Respond to an enter key press. Prevent the bubbling of the enter key
+            // press to the button group parent element.
+            if (event.keyCode === 13) {
+                event.stopPropagation();
+            }
+
+            // Only take action when a direction key is pressed.
+            if (_.indexOf(_.union(upDownKeys, leftRightKeys), event.keyCode) > -1) {
+                var view = this;
+                var $target = $(event.currentTarget);
+                var $button = $target.parent();
+                var $container = $button.parent();
+                var $group = $button.closest('.ckeditor-toolbar-group');
+                var $row = $button.closest('.ckeditor-row');
+                var containerType = $container.data('drupal-ckeditor-button-sorting');
+                var $availableButtons = this.$el.find('[data-drupal-ckeditor-button-sorting="source"]');
+                var $activeButtons = this.$el.find('.ckeditor-toolbar-active');
+                // The current location of the button, just in case it needs to be put
+                // back.
+                var $originalGroup = $group;
+                var dir;
+
+                // Move available buttons between their container and the active toolbar.
+                if (containerType === 'source') {
+                    // Move the button to the active toolbar configuration when the down or
+                    // up keys are pressed.
+                    if (_.indexOf([40, 63233], event.keyCode) > -1) {
+                        // Move the button to the first row, first button group index
+                        // position.
+                        $activeButtons.find('.ckeditor-toolbar-group-buttons').eq(0).prepend($button);
+                    }
+                }
+                else if (containerType === 'target') {
+                    // Move buttons between sibling buttons in a group and between groups.
+                    if (_.indexOf(leftRightKeys, event.keyCode) > -1) {
+                        // Move left.
+                        var $siblings = $container.children();
+                        var index = $siblings.index($button);
+                        if (_.indexOf([37, 63234], event.keyCode) > -1) {
+                            // Move between sibling buttons.
+                            if (index > 0) {
+                                $button.insertBefore($container.children().eq(index - 1));
+                            }
+                            // Move between button groups and rows.
+                            else {
+                                // Move between button groups.
+                                $group = $container.parent().prev();
+                                if ($group.length > 0) {
+                                    $group.find('.ckeditor-toolbar-group-buttons').append($button);
+                                }
+                                // Wrap between rows.
+                                else {
+                                    $container.closest('.ckeditor-row').prev().find('.ckeditor-toolbar-group').not('.placeholder').find('.ckeditor-toolbar-group-buttons').eq(-1).append($button);
+                                }
+                            }
+                        }
+                        // Move right.
+                        else if (_.indexOf([39, 63235], event.keyCode) > -1) {
+                            // Move between sibling buttons.
+                            if (index < ($siblings.length - 1)) {
+                                $button.insertAfter($container.children().eq(index + 1));
+                            }
+                            // Move between button groups. Moving right at the end of a row
+                            // will create a new group.
+                            else {
+                                $container.parent().next().find('.ckeditor-toolbar-group-buttons').prepend($button);
+                            }
+                        }
+                    }
+                    // Move buttons between rows and the available button set.
+                    else if (_.indexOf(upDownKeys, event.keyCode) > -1) {
+                        dir = (_.indexOf([38, 63232], event.keyCode) > -1) ? 'prev' : 'next';
+                        $row = $container.closest('.ckeditor-row')[dir]();
+                        // Move the button back into the available button set.
+                        if (dir === 'prev' && $row.length === 0) {
+                            // If this is a divider, just destroy it.
+                            if ($button.data('drupal-ckeditor-type') === 'separator') {
+                                $button
+                                    .off()
+                                    .remove();
+                                // Focus on the first button in the active toolbar.
+                                $activeButtons.find('.ckeditor-toolbar-group-buttons').eq(0).children().eq(0).children().trigger('focus');
+                            }
+                            // Otherwise, move it.
+                            else {
+                                $availableButtons.prepend($button);
+                            }
+                        }
+                        else {
+                            $row.find('.ckeditor-toolbar-group-buttons').eq(0).prepend($button);
+                        }
+                    }
+                }
+                // Move dividers between their container and the active toolbar.
+                else if (containerType === 'dividers') {
+                    // Move the button to the active toolbar configuration when the down or
+                    // up keys are pressed.
+                    if (_.indexOf([40, 63233], event.keyCode) > -1) {
+                        // Move the button to the first row, first button group index
+                        // position.
+                        $button = $button.clone(true);
+                        $activeButtons.find('.ckeditor-toolbar-group-buttons').eq(0).prepend($button);
+                        $target = $button.children();
+                    }
+                }
+
+                view = this;
+                // Attempt to move the button to the new toolbar position.
+                Drupal.ckeditor.registerButtonMove(this, $button, function (result) {
+
+                    // Put the button back if the registration failed.
+                    // If the button was in a row, then it was in the active toolbar
+                    // configuration. The button was probably placed in a new group, but
+                    // that action was canceled.
+                    if (!result && $originalGroup) {
+                        $originalGroup.find('.ckeditor-buttons').append($button);
+                    }
+                    // Otherwise refresh the sortables to acknowledge the new button
+                    // positions.
+                    else {
+                        view.$el.find('.ui-sortable').sortable('refresh');
+                    }
+                    // Refocus the target button so that the user can continue from a known
+                    // place.
+                    $target.trigger('focus');
+                });
+
+                event.preventDefault();
+                event.stopPropagation();
+            }
+        },
+
+        /**
+         * Handles keypresses on a CKEditor configuration group.
+         *
+         * @param jQuery.Event event
+         */
+        onPressGroup: function (event) {
+            var upDownKeys = [
+                38, // Up arrow.
+                63232, // Safari up arrow.
+                40, // Down arrow.
+                63233 // Safari down arrow.
+            ];
+            var leftRightKeys = [
+                37, // Left arrow.
+                63234, // Safari left arrow.
+                39, // Right arrow.
+                63235 // Safari right arrow.
+            ];
+
+            // Respond to an enter key press.
+            if (event.keyCode === 13) {
+                var view = this;
+                // Open the group renaming dialog in the next evaluation cycle so that
+                // this event can be cancelled and the bubbling wiped out. Otherwise,
+                // Firefox has issues because the page focus is shifted to the dialog
+                // along with the keydown event.
+                window.setTimeout(function () {
+                    Drupal.ckeditor.openGroupNameDialog(view, $(event.currentTarget));
+                }, 0);
+                event.preventDefault();
+                event.stopPropagation();
+            }
+
+            // Respond to direction key presses.
+            if (_.indexOf(_.union(upDownKeys, leftRightKeys), event.keyCode) > -1) {
+                var $group = $(event.currentTarget);
+                var $container = $group.parent();
+                var $siblings = $container.children();
+                var index, dir;
+                // Move groups between sibling groups.
+                if (_.indexOf(leftRightKeys, event.keyCode) > -1) {
+                    index = $siblings.index($group);
+                    // Move left between sibling groups.
+                    if ((_.indexOf([37, 63234], event.keyCode) > -1)) {
+                        if (index > 0) {
+                            $group.insertBefore($siblings.eq(index - 1));
+                        }
+                        // Wrap between rows. Insert the group before the placeholder group
+                        // at the end of the previous row.
+                        else {
+                            $group.insertBefore($container.closest('.ckeditor-row').prev().find('.ckeditor-toolbar-groups').children().eq(-1));
+                        }
+                    }
+                    // Move right between sibling groups.
+                    else if (_.indexOf([39, 63235], event.keyCode) > -1) {
+                        // Move to the right if the next group is not a placeholder.
+                        if (!$siblings.eq(index + 1).hasClass('placeholder')) {
+                            $group.insertAfter($container.children().eq(index + 1));
+                        }
+                        // Wrap group between rows.
+                        else {
+                            $container.closest('.ckeditor-row').next().find('.ckeditor-toolbar-groups').prepend($group);
+                        }
+                    }
+
+                }
+                // Move groups between rows.
+                else if (_.indexOf(upDownKeys, event.keyCode) > -1) {
+                    dir = (_.indexOf([38, 63232], event.keyCode) > -1) ? 'prev' : 'next';
+                    $group.closest('.ckeditor-row')[dir]().find('.ckeditor-toolbar-groups').eq(0).prepend($group);
+                }
+
+                Drupal.ckeditor.registerGroupMove(this, $group);
+                $group.trigger('focus');
+                event.preventDefault();
+                event.stopPropagation();
+            }
+        }
+    });
+
+})(Drupal, Backbone, jQuery);
diff --git a/core/modules/ckeditor/js/views/VisualView.js b/core/modules/ckeditor/js/views/VisualView.js
new file mode 100644
index 0000000..f3c48d2
--- /dev/null
+++ b/core/modules/ckeditor/js/views/VisualView.js
@@ -0,0 +1,253 @@
+/**
+ * @file
+ * A Backbone View that provides the visual UX view of CKEditor toolbar configuration.
+ */
+
+(function (Drupal, Backbone, $) {
+
+    "use strict";
+
+    /**
+     * Backbone View for CKEditor toolbar configuration; visual UX.
+     */
+    Drupal.ckeditor.VisualView = Backbone.View.extend({
+
+        events: {
+            'click .ckeditor-toolbar-group-name': 'onGroupNameClick',
+            'click .ckeditor-groupnames-toggle': 'onGroupNamesToggleClick',
+            'click .ckeditor-add-new-group button': 'onAddGroupButtonClick'
+        },
+
+        /**
+         * {@inheritdoc}
+         */
+        initialize: function () {
+            this.listenTo(this.model, 'change:isDirty change:groupNamesVisible', this.render);
+
+            // Add a toggle for the button group names.
+            $(Drupal.theme('ckeditorButtonGroupNamesToggle'))
+                .prependTo(this.$el.find('#ckeditor-active-toolbar').parent());
+
+            this.render();
+        },
+
+        /**
+         * {@inheritdoc}
+         */
+        render: function (model, value, changedAttributes) {
+            this.insertPlaceholders();
+            this.applySorting();
+
+            // Toggle button group names.
+            var groupNamesVisible = this.model.get('groupNamesVisible');
+            // If a button was just placed in the active toolbar, ensure that the
+            // button group names are visible.
+            if (changedAttributes && changedAttributes.changes && changedAttributes.changes.isDirty) {
+                this.model.set({groupNamesVisible: true}, {silent: true});
+                groupNamesVisible = true;
+            }
+            this.$el.find('[data-toolbar="active"]').toggleClass('ckeditor-group-names-are-visible', groupNamesVisible);
+            this.$el.find('.ckeditor-groupnames-toggle')
+                .text((groupNamesVisible) ? Drupal.t('Hide group names') : Drupal.t('Show group names'))
+                .attr('aria-pressed', groupNamesVisible);
+
+            return this;
+        },
+
+        /**
+         * Handles clicks to a button group name.
+         *
+         * @param jQuery.Event event
+         */
+        onGroupNameClick: function (event) {
+            var $group = $(event.currentTarget).closest('.ckeditor-toolbar-group');
+            Drupal.ckeditor.openGroupNameDialog(this, $group);
+
+            event.stopPropagation();
+            event.preventDefault();
+        },
+
+        /**
+         * Handles clicks on the button group names toggle button.
+         */
+        onGroupNamesToggleClick: function (event) {
+            this.model.set('groupNamesVisible', !this.model.get('groupNamesVisible'));
+            event.preventDefault();
+        },
+
+        /**
+         * Prompts the user to provide a name for a new button group; inserts it.
+         *
+         * @param jQuery.Event event
+         */
+        onAddGroupButtonClick: function (event) {
+
+            /**
+             * Inserts a new button if the openGroupNameDialog function returns true.
+             *
+             * @param Boolean success
+             *   A flag that indicates if the user created a new group (true) or
+             *   canceled out of the dialog (false).
+             * @param jQuery $group
+             *   A jQuery DOM fragment that represents the new button group. It has
+             *   not been added to the DOM yet.
+             */
+            function insertNewGroup(success, $group) {
+                if (success) {
+                    $group.appendTo($(event.currentTarget).closest('.ckeditor-row').children('.ckeditor-toolbar-groups'));
+                    // Focus on the new group.
+                    $group.trigger('focus');
+                }
+            }
+
+            // Pass in a DOM fragment of a placeholder group so that the new group
+            // name can be applied to it.
+            Drupal.ckeditor.openGroupNameDialog(this, $(Drupal.theme('ckeditorToolbarGroup')), insertNewGroup);
+
+            event.preventDefault();
+        },
+
+        /**
+         * Handles jQuery Sortable stop sort of a button group.
+         *
+         * @param jQuery.Event event
+         * @param Object ui
+         *   A jQuery.ui.sortable argument that contains information about the
+         *   elements involved in the sort action.
+         */
+        endGroupDrag: function (event, ui) {
+            var view = this;
+            Drupal.ckeditor.registerGroupMove(this, ui.item, function (success) {
+                if (!success) {
+                    // Cancel any sorting in the configuration area.
+                    view.$el.find('.ckeditor-toolbar-configuration').find('.ui-sortable').sortable('cancel');
+                }
+            });
+        },
+
+        /**
+         * Handles jQuery Sortable start sort of a button.
+         *
+         * @param jQuery.Event event
+         * @param Object ui
+         *   A jQuery.ui.sortable argument that contains information about the
+         *   elements involved in the sort action.
+         */
+        startButtonDrag: function (event, ui) {
+            this.$el.find('a:focus').trigger('blur');
+
+            // Show the button group names as soon as the user starts dragging.
+            this.model.set('groupNamesVisible', true);
+        },
+
+        /**
+         * Handles jQuery Sortable stop sort of a button.
+         *
+         * @param jQuery.Event event
+         * @param Object ui
+         *   A jQuery.ui.sortable argument that contains information about the
+         *   elements involved in the sort action.
+         */
+        endButtonDrag: function (event, ui) {
+            var view = this;
+            Drupal.ckeditor.registerButtonMove(this, ui.item, function (success) {
+                if (!success) {
+                    // Cancel any sorting in the configuration area.
+                    view.$el.find('.ui-sortable').sortable('cancel');
+                }
+                // Refocus the target button so that the user can continue from a known
+                // place.
+                ui.item.find('a').trigger('focus');
+            });
+        },
+
+        /**
+         * Invokes jQuery.sortable() on new buttons and groups in a CKEditor config.
+         */
+        applySorting: function () {
+            // Make the buttons sortable.
+            this.$el.find('.ckeditor-buttons').not('.ui-sortable').sortable({
+                // Change this to .ckeditor-toolbar-group-buttons.
+                connectWith: '.ckeditor-buttons',
+                placeholder: 'ckeditor-button-placeholder',
+                forcePlaceholderSize: true,
+                tolerance: 'pointer',
+                cursor: 'move',
+                start: this.startButtonDrag.bind(this),
+                // Sorting within a sortable.
+                stop: this.endButtonDrag.bind(this)
+            }).disableSelection();
+
+            // Add the drag and drop functionality to button groups.
+            this.$el.find('.ckeditor-toolbar-groups').not('.ui-sortable').sortable({
+                connectWith: '.ckeditor-toolbar-groups',
+                cancel: '.ckeditor-add-new-group',
+                placeholder: 'ckeditor-toolbar-group-placeholder',
+                forcePlaceholderSize: true,
+                cursor: 'move',
+                stop: this.endGroupDrag.bind(this)
+            });
+
+            // Add the drag and drop functionality to buttons.
+            this.$el.find('.ckeditor-multiple-buttons li').draggable({
+                connectToSortable: '.ckeditor-toolbar-active .ckeditor-buttons',
+                helper: 'clone'
+            });
+        },
+
+        /**
+         * Wraps the invocation of methods to insert blank groups and rows.
+         */
+        insertPlaceholders: function () {
+            this.insertPlaceholderRow();
+            this.insertNewGroupButtons();
+        },
+
+        /**
+         * Inserts a blank row at the bottom of the CKEditor configuration.
+         */
+        insertPlaceholderRow: function () {
+            var $rows = this.$el.find('.ckeditor-row');
+            // Add a placeholder row. to the end of the list if one does not exist.
+            if (!$rows.eq(-1).hasClass('placeholder')) {
+                this.$el
+                    .find('.ckeditor-toolbar-active')
+                    .children('.ckeditor-active-toolbar-configuration')
+                    .append(Drupal.theme('ckeditorRow'));
+            }
+            // Update the $rows variable to include the new row.
+            $rows = this.$el.find('.ckeditor-row');
+            // Remove blank rows except the last one.
+            var len = $rows.length;
+            $rows.filter(function (index, row) {
+                // Do not remove the last row.
+                if (index + 1 === len) {
+                    return false;
+                }
+                return $(row).find('.ckeditor-toolbar-group').not('.placeholder').length === 0;
+            })
+                // Then get all rows that are placeholders and remove them.
+                .remove();
+        },
+
+        /**
+         * Inserts a button in each row that will add a new CKEditor button group.
+         */
+        insertNewGroupButtons: function () {
+            // Insert an add group button to each row.
+            this.$el.find('.ckeditor-row').each(function () {
+                var $row = $(this);
+                var $groups = $row.find('.ckeditor-toolbar-group');
+                var $button = $row.find('.ckeditor-add-new-group');
+                if ($button.length === 0) {
+                    $row.children('.ckeditor-toolbar-groups').append(Drupal.theme('ckeditorNewButtonGroup'));
+                }
+                // If a placeholder group exists, make sure it's at the end of the row.
+                else if (!$groups.eq(-1).hasClass('ckeditor-add-new-group')) {
+                    $button.appendTo($row.children('.ckeditor-toolbar-groups'));
+                }
+            });
+        }
+    });
+
+})(Drupal, Backbone, jQuery);
