diff --git a/core/modules/ckeditor/src/Plugin/Editor/CKEditor.php b/core/modules/ckeditor/src/Plugin/Editor/CKEditor.php
index 255691f..42dbb00 100644
--- a/core/modules/ckeditor/src/Plugin/Editor/CKEditor.php
+++ b/core/modules/ckeditor/src/Plugin/Editor/CKEditor.php
@@ -10,6 +10,7 @@
 use Drupal\Core\Render\RendererInterface;
 use Drupal\editor\Plugin\EditorBase;
 use Drupal\Core\Plugin\ContainerFactoryPluginInterface;
+use Drupal\Core\State\StateInterface;
 use Drupal\editor\Entity\Editor;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
@@ -58,6 +59,13 @@ class CKEditor extends EditorBase implements ContainerFactoryPluginInterface {
   protected $renderer;
 
   /**
+   * The state key/value store.
+   *
+   * @var \Drupal\Core\State\StateInterface
+   */
+  protected $state;
+
+  /**
    * Constructs a Drupal\Component\Plugin\PluginBase object.
    *
    * @param array $configuration
@@ -74,13 +82,16 @@ class CKEditor extends EditorBase implements ContainerFactoryPluginInterface {
    *   The language manager.
    * @param \Drupal\Core\Render\RendererInterface $renderer
    *   The renderer.
+   * @param \Drupal\Core\State\StateInterface $state
+   *   The state key/value store.
    */
-  public function __construct(array $configuration, $plugin_id, $plugin_definition, CKEditorPluginManager $ckeditor_plugin_manager, ModuleHandlerInterface $module_handler, LanguageManagerInterface $language_manager, RendererInterface $renderer) {
+  public function __construct(array $configuration, $plugin_id, $plugin_definition, CKEditorPluginManager $ckeditor_plugin_manager, ModuleHandlerInterface $module_handler, LanguageManagerInterface $language_manager, RendererInterface $renderer, StateInterface $state) {
     parent::__construct($configuration, $plugin_id, $plugin_definition);
     $this->ckeditorPluginManager = $ckeditor_plugin_manager;
     $this->moduleHandler = $module_handler;
     $this->languageManager = $language_manager;
     $this->renderer = $renderer;
+    $this->state = $state;
   }
 
   /**
@@ -94,7 +105,8 @@ public static function create(ContainerInterface $container, array $configuratio
       $container->get('plugin.manager.ckeditor.plugin'),
       $container->get('module_handler'),
       $container->get('language_manager'),
-      $container->get('renderer')
+      $container->get('renderer'),
+      $container->get('state')
     );
   }
 
@@ -423,6 +435,10 @@ public function buildContentsCssJSSetting(Editor $editor) {
     }, []);
     $css = array_merge($css, $plugins_css);
     $css = array_merge($css, _ckeditor_theme_css());
+    $query_string = '?' . $this->state->get('system.css_js_query_string') ?: '0';
+    $css = array_map(function($item) use($query_string) {
+      return $item . $query_string;
+    }, $css);
     $css = array_map('file_create_url', $css);
     $css = array_map('file_url_transform_relative', $css);