diff --git a/composer.json b/composer.json
index 2a444d0..8f961bd 100644
--- a/composer.json
+++ b/composer.json
@@ -1,7 +1,7 @@
 {
   "name": "bnomei/kirby3-security-headers",
   "type": "kirby-plugin",
-  "version": "2.4.0",
+  "version": "2.4.1",
   "license": "MIT",
   "description": "Kirby 3 Plugin for easier Security Headers setup",
   "authors": [
diff --git a/index.php b/index.php
index ca8b036..6678f15 100644
--- a/index.php
+++ b/index.php
@@ -86,7 +86,7 @@
         },
     ],
     'pageMethods' => [
-        'nonce' => function (string $key): string {
+        'nonce' => function (string $key): ?string {
             return \Bnomei\SecurityHeaders::singleton()->getNonce($key);
         },
         'nonceAttr' => function (string $key): string {