diff -u b/core/modules/locale/locale.module b/core/modules/locale/locale.module
--- b/core/modules/locale/locale.module
+++ b/core/modules/locale/locale.module
@@ -500,7 +500,7 @@
   }
 
   // Replace the placeholder file with the actual JS translation file.
-  $placeholder_file = 'core/modules/locale/locale.translation.js';
+  $placeholder_file = 'core/modules/locale/js/locale.translation.js';
   if (isset($javascript[$placeholder_file])) {
     if ($translation_file = locale_js_translate($files)) {
       $js_translation_asset = &$javascript[$placeholder_file];