diff --git a/core/modules/file/file.module b/core/modules/file/file.module
index 94ddc49..488ee57 100644
--- a/core/modules/file/file.module
+++ b/core/modules/file/file.module
@@ -856,11 +856,12 @@ function file_save_upload($form_field_name, $validators = array(), $destination
           '#theme' => 'item_list',
           '#items' => $errors,
         );
-        $message = SafeMarkup::set($message . drupal_render($item_list));
+        $error_text = drupal_render($item_list);
       }
       else {
-        $message = SafeMarkup::set($message . ' ' . SafeMarkup::escape(array_pop($errors)));
+        $error_text = array_pop($errors);
       }
+      $message = SafeMarkup::format('@message @error_text', ['@message' => $message, '@error_text' => $error_text]);
       drupal_set_message($message, 'error');
       $files[$i] = FALSE;
       continue;