diff --git a/Controllers/Backend/Adminer.php b/Controllers/Backend/Adminer.php
index 55ae5b2..3836e0d 100644
--- a/Controllers/Backend/Adminer.php
+++ b/Controllers/Backend/Adminer.php
@@ -22,7 +22,11 @@ public function formAction()
         $baseUrl = Shopware()->Front()->Router()->assemble(['controller' => 'index']);
         $baseUrl = str_replace('/backend', '', $baseUrl);
 
-        $shopwarePath = Shopware()->Container()->getParameter('kernel.root_dir');
+        if (mb_substr($baseUrl, -1) !== '/') {
+            $baseUrl .= '/';
+        }
+
+        $shopwarePath = Shopware()->Container()->getParameter('shopware.app.rootdir');
         $filePath = dirname(dirname(__DIR__));
         $pathToPluginFolder = str_ireplace($shopwarePath, '', $filePath);