diff --git a/Classes/ViewHelpers/LoginFormViewHelper.php b/Classes/ViewHelpers/LoginFormViewHelper.php
index 0bc68e98..b50b7199 100644
--- a/Classes/ViewHelpers/LoginFormViewHelper.php
+++ b/Classes/ViewHelpers/LoginFormViewHelper.php
@@ -205,13 +205,12 @@ protected function addFieldNamePrefixToViewHelperVariableContainer(): void
     /**
      * Renders a hidden form field containing the technical identity of the given object.
      *
-     * @param object $object Object to create the identity field for
-     * @param string $name Name
-     *
-     * @return string A hidden field containing the Identity (UID in TYPO3 Flow, uid in Extbase) of the given object or NULL if the object is unknown to the persistence framework
+     * @param mixed $object Object to create the identity field for. Non-objects are ignored.
+     * @param string|null $name Name
+     * @return string A hidden field containing the Identity (uid) of the given object
      * @see \TYPO3\CMS\Extbase\Mvc\Controller\Argument::setValue()
      */
-    protected function renderHiddenIdentityField(?object $object, ?string $name): string
+    protected function renderHiddenIdentityField(mixed $object, ?string $name): string
     {
         if ($object instanceof LazyLoadingProxy) {
             $object = $object->_loadRealInstance();
diff --git a/composer.json b/composer.json
index 3eada16e..2950f3fb 100644
--- a/composer.json
+++ b/composer.json
@@ -49,7 +49,7 @@
     "typo3/coding-standards": "^0.8"
   },
   "conflict": {
-    "typo3/cms-core": "<12.4.3"
+    "typo3/cms-core": "<12.4.20"
   },
   "config": {
     "preferred-install": {