diff --git a/includes/page_editmod.php b/includes/page_editmod.php
index 4941509..9f9db51 100644
--- a/includes/page_editmod.php
+++ b/includes/page_editmod.php
@@ -75,7 +75,7 @@ if ($_SERVER['REQUEST_METHOD'] == 'POST') {
               }
             }
           } else {
-            $fileExtension = str_replace(['/', '\\'], '', $modDataToEdit['image_ext']);
+            $fileExtension = $modDataToEdit['image_ext'] ? str_replace(['/', '\\'], '', $modDataToEdit['image_ext']) : null;
             $liveCoverImagePathname = $modUploadDirectory . '/' . str_replace(['/', '\\'], '', $modDataToEdit['slug']) . '.' . $fileExtension;
             if (file_exists($liveCoverImagePathname)) {
               if (!file_exists($modPendingUploadDirectory) && !mkdir($modPendingUploadDirectory, 0777, true)) {