diff --git a/core/modules/node/node.module b/core/modules/node/node.module
index c523485..c56236e 100644
--- a/core/modules/node/node.module
+++ b/core/modules/node/node.module
@@ -171,7 +171,7 @@ function node_theme() {
  * @endcode
  */
 function node_library_info_alter(&$libraries, $extension) {
-  if ($extension === 'node' && isset($libraries['drupal.node.preview'])) {
+  if ($extension === 'node' && isset($libraries['drupal.node.preview']) && Drupal::config('system.theme')->get('admin') != '0' ) {
     $theme = Drupal::config('system.theme')->get('admin');
 
     // First let the base theme modify the library, then the actual theme.