diff --git a/Classes/TypoScript/Loader.php b/Classes/TypoScript/Loader.php
index 9ffee8c..7398ff1 100644
--- a/Classes/TypoScript/Loader.php
+++ b/Classes/TypoScript/Loader.php
@@ -47,7 +47,7 @@ public function __construct(PackageHelper $packageHelper)
     public function addSiteConfiguration(&$hookParameters, TemplateService $templateService)
     {
         // let's copy the rootline value, as $templateService->processTemplate() might reset it
-        $rootLine = $hookParameters['rootLine'];
+        $rootLine = $hookParameters['rootLine'] ?? null;
         if (!is_array($rootLine) || empty($rootLine)) {
             return;
         }