diff --git a/composer.json b/composer.json
index 9e260c5..60030e4 100644
--- a/composer.json
+++ b/composer.json
@@ -90,5 +90,12 @@
       "@chain",
       "yarn build"
     ]
+  },
+  "config": {
+    "allow-plugins": {
+      "contao-components/installer": true,
+      "bamarni/composer-bin-plugin": true,
+      "contao/manager-plugin": true
+    }
   }
 }
diff --git a/src/Controller/DisplayRecordsController.php b/src/Controller/DisplayRecordsController.php
index d85f305..df0cb82 100644
--- a/src/Controller/DisplayRecordsController.php
+++ b/src/Controller/DisplayRecordsController.php
@@ -46,8 +46,7 @@ public function question(Request $request, int $id): Response
             throw $this->createAccessDeniedException();
         }
 
-        $stateParameter = $request->get('state');
-        $overwriteState = null !== $stateParameter ? (bool) $stateParameter : null;
+        $overwriteState = $request->query->has('state') ? (bool) $request->query->get('state') : null;
 
         /** @var Question|null $question */
         $question = $this->questionRepository->find($id);
diff --git a/src/Controller/SurveyFragment.php b/src/Controller/SurveyFragment.php
index d6f29f0..7267911 100644
--- a/src/Controller/SurveyFragment.php
+++ b/src/Controller/SurveyFragment.php
@@ -22,6 +22,7 @@
 use Mvo\ContaoSurvey\Form\SurveyManagerFactory;
 use Mvo\ContaoSurvey\Registry;
 use Mvo\ContaoSurvey\Repository\SurveyRepository;
+use Symfony\Component\Form\SubmitButton;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Contracts\EventDispatcher\EventDispatcherInterface;
@@ -127,14 +128,20 @@ private function proceedUntilCompleted(SurveyManager $manager): bool
         }
 
         // reset (back to the first step)
-        if ($manager->form['reset']->isClicked()) {
+        /** @var SubmitButton $resetButton */
+        $resetButton = $manager->form['reset'];
+
+        if ($resetButton->isClicked()) {
             $manager->reset();
 
             return false;
         }
 
         // back to the previous step
-        if (isset($manager->form['previous']) && $manager->form['previous']->isClicked() && $manager->previousStep()) {
+        /** @var SubmitButton|null $backButton */
+        $backButton = $manager->form['previous'] ?? null;
+
+        if ($backButton && $backButton->isClicked() && $manager->previousStep()) {
             return false;
         }
 
diff --git a/src/DependencyInjection/Compiler/RegisterSessionStoragePass.php b/src/DependencyInjection/Compiler/RegisterSessionStoragePass.php
deleted file mode 100644
index fecc5df..0000000
--- a/src/DependencyInjection/Compiler/RegisterSessionStoragePass.php
+++ /dev/null
@@ -1,27 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-/*
- * @author  Moritz Vondano
- * @license MIT
- */
-
-namespace Mvo\ContaoSurvey\DependencyInjection\Compiler;
-
-use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
-use Symfony\Component\DependencyInjection\ContainerBuilder;
-use Symfony\Component\DependencyInjection\Reference;
-
-class RegisterSessionStoragePass implements CompilerPassInterface
-{
-    public function process(ContainerBuilder $container): void
-    {
-        if (!$container->hasDefinition('session')) {
-            return;
-        }
-
-        $session = $container->findDefinition('session');
-        $session->addMethodCall('registerBag', [new Reference('mvo.survey.session_storage')]);
-    }
-}
diff --git a/src/MvoContaoSurveyBundle.php b/src/MvoContaoSurveyBundle.php
index 653448a..a586c53 100644
--- a/src/MvoContaoSurveyBundle.php
+++ b/src/MvoContaoSurveyBundle.php
@@ -9,7 +9,6 @@
 
 namespace Mvo\ContaoSurvey;
 
-use Mvo\ContaoSurvey\DependencyInjection\Compiler\RegisterSessionStoragePass;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\HttpKernel\Bundle\Bundle;
 
@@ -18,7 +17,5 @@ class MvoContaoSurveyBundle extends Bundle
     public function build(ContainerBuilder $container): void
     {
         parent::build($container);
-
-        $container->addCompilerPass(new RegisterSessionStoragePass());
     }
 }