diff --git a/modules/markup/file_preview.go b/modules/markup/file_preview.go
index 167bbd199..377809529 100644
--- a/modules/markup/file_preview.go
+++ b/modules/markup/file_preview.go
@@ -1,3 +1,6 @@
+// Copyright The Forgejo Authors.
+// SPDX-License-Identifier: MIT
+
 package markup
 
 import (