diff --git a/app/helpers/functions.mts b/app/helpers/functions.mts
index 32601299..b7b3943f 100644
--- a/app/helpers/functions.mts
+++ b/app/helpers/functions.mts
@@ -198,7 +198,7 @@ const defaultViewerForFile = (file: string) => {
   if (isMsOfficeViewerSupported(file)) {
     return "ms-office-viewer";
   }
-  else if (path.extname(file).search(/^((?:.pdf))$/ig) != -1) {
+  else {
     return "built-in";
   }
 }