diff --git a/core/modules/ckeditor/src/Plugin/Editor/CKEditor.php b/core/modules/ckeditor/src/Plugin/Editor/CKEditor.php
index f84054c..4ea40a6 100644
--- a/core/modules/ckeditor/src/Plugin/Editor/CKEditor.php
+++ b/core/modules/ckeditor/src/Plugin/Editor/CKEditor.php
@@ -295,6 +295,8 @@ public function getJSSettings(EditorEntity $editor) {
       // styles.js by default.
       // See http://dev.ckeditor.com/ticket/9992#comment:9.
       'stylesSet' => FALSE,
+      // Don't load CKEditor's config.js file.
+      'customConfig' => '',
     );
 
     // Finally, set Drupal-specific CKEditor settings.