diff --git a/modules/mod_random_image/src/Helper/RandomImageHelper.php b/modules/mod_random_image/src/Helper/RandomImageHelper.php
index 0345f26a1d9bd..4d49952e0275c 100644
--- a/modules/mod_random_image/src/Helper/RandomImageHelper.php
+++ b/modules/mod_random_image/src/Helper/RandomImageHelper.php
@@ -82,7 +82,14 @@ public static function getRandomImage(&$params, $images)
      */
     public static function getImages(&$params, $folder)
     {
-        $type   = $params->get('type', 'jpg');
+        $type       = $params->get('type', 'jpg');
+        $extensions = array_map('trim', explode(',', $type));
+
+        // Normalize to lowercase and strip leading dots
+        $extensions = array_map(function ($ext) {
+            return ltrim(strtolower($ext), '.');
+        }, $extensions);
+
         $files  = [];
         $images = [];
 
@@ -103,9 +110,14 @@ public static function getImages(&$params, $folder)
             $i = 0;
 
             foreach ($files as $img) {
-                if (!is_dir($dir . '/' . $img) && preg_match('/' . $type . '/', $img)) {
-                    $images[$i] = new \stdClass();
+                if (is_dir($dir . '/' . $img)) {
+                    continue;
+                }
+
+                $ext = pathinfo($img, PATHINFO_EXTENSION);
 
+                if (\in_array(strtolower($ext), $extensions, true)) {
+                    $images[$i]         = new \stdClass();
                     $images[$i]->name   = $img;
                     $images[$i]->folder = $folder;
                     $i++;