diff --git a/.github/workflows/test-application.yaml b/.github/workflows/test-application.yaml
index 373ce692..2d19efd2 100644
--- a/.github/workflows/test-application.yaml
+++ b/.github/workflows/test-application.yaml
@@ -31,8 +31,26 @@ jobs:
                       dependency-versions: 'highest'
                       tools: 'composer:v2'
                       env:
-                          SYMFONY_DEPRECATIONS_HELPER: weak
+                          SYMFONY_DEPRECATIONS_HELPER: disabled
 
+                    - php-version: '8.0'
+                      lint: true
+                      dependency-versions: 'highest'
+                      tools: 'composer:v2'
+                      env:
+                          SYMFONY_DEPRECATIONS_HELPER: disabled
+                    - php-version: '8.1'
+                      lint: true
+                      dependency-versions: 'highest'
+                      tools: 'composer:v2'
+                      env:
+                          SYMFONY_DEPRECATIONS_HELPER: disabled
+                    - php-version: '8.2'
+                      lint: true
+                      dependency-versions: 'highest'
+                      tools: 'composer:v2'
+                      env:
+                          SYMFONY_DEPRECATIONS_HELPER: weak
         services:
             mysql:
                 image: mysql:5.7
diff --git a/.gitignore b/.gitignore
index 5990b792..d2e292e4 100644
--- a/.gitignore
+++ b/.gitignore
@@ -32,5 +32,5 @@ Tests/Application/var
 Tests/Application/.env.test.local
 
 # php-cs-fixer
-.php_cs.cache
+.php-cs-fixer.cache
 php-cs-fixer
diff --git a/.php-cs-fixer.dist.php b/.php-cs-fixer.dist.php
new file mode 100644
index 00000000..62f43995
--- /dev/null
+++ b/.php-cs-fixer.dist.php
@@ -0,0 +1,49 @@
+<?php
+
+$header = <<<EOF
+This file is part of Sulu.
+
+(c) Sulu GmbH
+
+This source file is subject to the MIT license that is bundled
+with this source code in the file LICENSE.
+EOF;
+
+$finder = PhpCsFixer\Finder::create()
+    ->exclude(['var/cache', 'tests/Resources/cache', 'node_modules'])
+    ->in(__DIR__);
+
+$config = new PhpCsFixer\Config();
+$config->setRiskyAllowed(true)
+    ->setRules([
+        '@Symfony' => true,
+        'array_syntax' => ['syntax' => 'short'],
+        'class_definition' => false,
+        'concat_space' => ['spacing' => 'one'],
+        'function_declaration' => ['closure_function_spacing' => 'none'],
+        'header_comment' => ['header' => $header],
+        'native_constant_invocation' => true,
+        'native_function_casing' => true,
+        'native_function_invocation' => ['include' => ['@internal']],
+        'global_namespace_import' => ['import_classes' => false, 'import_constants' => false, 'import_functions' => false],
+        'no_superfluous_phpdoc_tags' => ['allow_mixed' => true, 'remove_inheritdoc' => true],
+        'ordered_imports' => true,
+        'phpdoc_align' => ['align' => 'left'],
+        'phpdoc_types_order' => false,
+        'single_line_throw' => false,
+        'single_line_comment_spacing' => false,
+        'phpdoc_to_comment' => [
+            'ignored_tags' => ['todo', 'var'],
+        ],
+        'phpdoc_separation' => [
+            'groups' => [
+                ['Serializer\\*', 'VirtualProperty', 'Accessor', 'Type', 'Groups', 'Expose', 'Exclude', 'SerializedName', 'Inline', 'ExclusionPolicy'],
+            ],
+        ],
+        'get_class_to_class_keyword' => false, // should be enabled as soon as support for php < 8 is dropped
+        'nullable_type_declaration_for_default_null_value' => true,
+        'no_null_property_initialization' => false,
+    ])
+    ->setFinder($finder);
+
+return $config;
diff --git a/.php_cs.dist b/.php_cs.dist
deleted file mode 100644
index 0bf9e0c5..00000000
--- a/.php_cs.dist
+++ /dev/null
@@ -1,28 +0,0 @@
-<?php
-
-$header = <<<EOF
-This file is part of Sulu.
-
-(c) Sulu GmbH
-
-This source file is subject to the MIT license that is bundled
-with this source code in the file LICENSE.
-EOF;
-
-$finder = PhpCsFixer\Finder::create()
-    ->exclude(['var/cache'])
-    ->in(__DIR__);
-
-return PhpCsFixer\Config::create()
-    ->setRules([
-        '@Symfony' => true,
-        'array_syntax' => ['syntax' => 'short'],
-        'class_definition' => false,
-        'concat_space' => ['spacing' => 'one'],
-        'function_declaration' => ['closure_function_spacing' => 'none'],
-        'header_comment' => ['header' => $header],
-        'ordered_imports' => true,
-        'phpdoc_align' => ['align' => 'left'],
-        'phpdoc_types_order' => false,
-    ])
-    ->setFinder($finder);
diff --git a/Admin/CommentAdmin.php b/Admin/CommentAdmin.php
index 2652981f..d8e69408 100644
--- a/Admin/CommentAdmin.php
+++ b/Admin/CommentAdmin.php
@@ -27,15 +27,15 @@
  */
 class CommentAdmin extends Admin
 {
-    const COMMENT_SECURITY_CONTEXT = 'sulu.comment.comments';
-    const COMMENT_LIST_VIEW = 'sulu_comment.comments.list';
-    const COMMENT_EDIT_FORM_VIEW = 'sulu_comment.comments.edit_form';
-    const COMMENT_EDIT_FORM_DETAILS_VIEW = 'sulu_comment.comments.edit_form.details';
+    public const COMMENT_SECURITY_CONTEXT = 'sulu.comment.comments';
+    public const COMMENT_LIST_VIEW = 'sulu_comment.comments.list';
+    public const COMMENT_EDIT_FORM_VIEW = 'sulu_comment.comments.edit_form';
+    public const COMMENT_EDIT_FORM_DETAILS_VIEW = 'sulu_comment.comments.edit_form.details';
 
-    const THREAD_SECURITY_CONTEXT = 'sulu.comment.threads';
-    const THREAD_LIST_VIEW = 'sulu_comment.threads.list';
-    const THREAD_EDIT_FORM_VIEW = 'sulu_comment.threads.edit_form';
-    const THREAD_EDIT_FORM_DETAILS_VIEW = 'sulu_comment.threads.edit_form.details';
+    public const THREAD_SECURITY_CONTEXT = 'sulu.comment.threads';
+    public const THREAD_LIST_VIEW = 'sulu_comment.threads.list';
+    public const THREAD_EDIT_FORM_VIEW = 'sulu_comment.threads.edit_form';
+    public const THREAD_EDIT_FORM_DETAILS_VIEW = 'sulu_comment.threads.edit_form.details';
 
     /**
      * @var ViewBuilderFactoryInterface
@@ -96,8 +96,7 @@ public function configureViews(ViewCollection $viewCollection): void
             new ToolbarAction('sulu_admin.delete'),
         ];
 
-        /** @var array $commentFormToolbarActions */
-        $commentFormToolbarActions = array_merge($formToolbarActions, [
+        $commentFormToolbarActions = \array_merge($formToolbarActions, [
             new TogglerToolbarAction(
                 $this->translator->trans('sulu_admin.publish', [], 'admin'),
                 'published',
diff --git a/Controller/CommentController.php b/Controller/CommentController.php
index 32c2fa36..91b70c97 100644
--- a/Controller/CommentController.php
+++ b/Controller/CommentController.php
@@ -105,23 +105,26 @@ public function cgetAction(Request $request): Response
         if ($threadType) {
             $listBuilder->in(
                 $fieldDescriptors['threadType'],
-                array_filter(explode(',', $threadType))
+                \array_filter(\explode(',', $threadType))
             );
 
             $request->query->remove('threadType');
         }
 
+        /** @var string $filterValue */
         foreach ($request->query->all() as $filterKey => $filterValue) {
             if (isset($fieldDescriptors[$filterKey])) {
                 $listBuilder->where($fieldDescriptors[$filterKey], $filterValue);
             }
         }
 
+        /** @var string $route */
+        $route = $request->attributes->get('_route');
         $results = $listBuilder->execute();
         $list = new ListRepresentation(
             $results,
             'comments',
-            $request->attributes->get('_route'),
+            $route,
             $request->query->all(),
             $listBuilder->getCurrentPage(),
             $listBuilder->getLimit(),
@@ -149,7 +152,9 @@ public function putAction(int $id, Request $request): Response
             throw new EntityNotFoundException(CommentInterface::class, $id);
         }
 
-        $comment->setMessage($request->request->get('message'));
+        /** @var string $message */
+        $message = $request->request->get('message');
+        $comment->setMessage($message);
 
         $this->commentManager->update($comment);
         $this->entityManager->flush();
@@ -163,8 +168,8 @@ public function cdeleteAction(Request $request): Response
         $ids = $request->query->get('ids', '');
 
         /** @var int[] $ids */
-        $ids = array_filter(explode(',', $ids));
-        if (0 === count($ids)) {
+        $ids = \array_filter(\explode(',', $ids));
+        if (0 === \count($ids)) {
             return $this->handleView($this->view(null, 204));
         }
 
diff --git a/Controller/ThreadController.php b/Controller/ThreadController.php
index 2fa4e5a6..8c1922a7 100644
--- a/Controller/ThreadController.php
+++ b/Controller/ThreadController.php
@@ -96,22 +96,26 @@ public function cgetAction(Request $request): Response
         $fieldDescriptors = $this->fieldDescriptorFactory->getFieldDescriptors('threads');
         $this->restHelper->initializeListBuilder($listBuilder, $fieldDescriptors);
 
+        /** @var string $filterValue */
         foreach ($request->query->all() as $filterKey => $filterValue) {
             if (isset($fieldDescriptors[$filterKey])) {
                 $listBuilder->where($fieldDescriptors[$filterKey], $filterValue);
             }
         }
 
+        /** @var string $typeParameter */
         $typeParameter = $request->get('types');
         if ($typeParameter) {
-            $listBuilder->in($fieldDescriptors['type'], array_filter(explode(',', $typeParameter)));
+            $listBuilder->in($fieldDescriptors['type'], \array_filter(\explode(',', $typeParameter)));
         }
 
         $items = $listBuilder->execute();
+        /** @var string $route */
+        $route = $request->attributes->get('_route');
         $list = new ListRepresentation(
             $items,
             'threads',
-            $request->attributes->get('_route'),
+            $route,
             $request->query->all(),
             $listBuilder->getCurrentPage(),
             $listBuilder->getLimit(),
@@ -139,7 +143,9 @@ public function putAction(int $id, Request $request): Response
             throw new EntityNotFoundException(ThreadInterface::class, $id);
         }
 
-        $thread->setTitle($request->request->get('title'));
+        /** @var string $title */
+        $title = $request->request->get('title');
+        $thread->setTitle($title);
 
         $this->commentManager->updateThread($thread);
         $this->entityManager->flush();
@@ -153,8 +159,8 @@ public function cdeleteAction(Request $request): Response
         $ids = $request->query->get('ids', '');
 
         /** @var int[] $ids */
-        $ids = array_filter(explode(',', $ids));
-        if (0 === count($ids)) {
+        $ids = \array_filter(\explode(',', $ids));
+        if (0 === \count($ids)) {
             return $this->handleView($this->view(null, 204));
         }
 
diff --git a/Controller/WebsiteCommentController.php b/Controller/WebsiteCommentController.php
index a199cbae..64542016 100644
--- a/Controller/WebsiteCommentController.php
+++ b/Controller/WebsiteCommentController.php
@@ -16,6 +16,7 @@
 use FOS\RestBundle\Controller\Annotations\Post;
 use FOS\RestBundle\Controller\Annotations\RouteResource;
 use FOS\RestBundle\Routing\ClassResourceInterface;
+use FOS\RestBundle\View\View;
 use FOS\RestBundle\View\ViewHandlerInterface;
 use Sulu\Bundle\CommentBundle\Entity\Comment;
 use Sulu\Bundle\CommentBundle\Entity\CommentInterface;
@@ -65,17 +66,17 @@ class WebsiteCommentController extends AbstractRestController implements ClassRe
     private $commentClass;
 
     /**
-     * @var array
+     * @var array<string, array<string, mixed|mixed[]>>
      */
     private $commentTypes;
 
     /**
-     * @var array
+     * @var array<string, string>
      */
     private $commentDefaultTemplates;
 
     /**
-     * @var array
+     * @var array<string>
      */
     private $commentSerializationGroups;
 
@@ -84,6 +85,11 @@ class WebsiteCommentController extends AbstractRestController implements ClassRe
      */
     private $enableNestedCommentsDefault;
 
+    /**
+     * @param array<string, array<string, mixed|mixed[]>> $commentTypes
+     * @param array<string, string> $commentDefaultTemplates
+     * @param array<string> $commentSerializationGroups
+     */
     public function __construct(
         ViewHandlerInterface $viewHandler,
         CommentManagerInterface $commentManager,
@@ -118,19 +124,20 @@ public function cgetCommentsAction(string $threadId, Request $request): Response
     {
         list($type, $entityId) = $this->getThreadIdParts($threadId);
 
-        $limit = $request->query->getInt('limit') ?? 10;
-        $offset = $request->query->getInt('offset') ?? 0;
+        $limit = $request->query->getInt('limit', 10);
+        $offset = $request->query->getInt('offset', 0);
 
+        /** @var null|int $pageSize */
         $pageSize = $request->get('pageSize');
         if ($pageSize) {
-            @\trigger_deprecation('sulu/comment-bundle', '2.x', 'The usage of the "pageSize" parameter is deprecated.
+            @trigger_deprecation('sulu/comment-bundle', '2.x', 'The usage of the "pageSize" parameter is deprecated.
         Please use "limit" and "offset instead.');
             $limit = $pageSize;
         }
 
         $page = $request->get('page');
         if ($page) {
-            @\trigger_deprecation('sulu/comment-bundle', '2.x', 'The usage of the "page" parameter is deprecated.
+            @trigger_deprecation('sulu/comment-bundle', '2.x', 'The usage of the "page" parameter is deprecated.
             Please use "limit" and "offset instead.');
 
             $offset = ($page - 1) * $limit;
@@ -166,7 +173,7 @@ public function cgetCommentsAction(string $threadId, Request $request): Response
             ]
         );
 
-        $contentData = array_merge(
+        $contentData = \array_merge(
             [
                 'form' => $form->createView(),
                 'nestedComments' => $this->getNestedCommentsEnabled($type),
@@ -238,7 +245,9 @@ public function postCommentsAction(string $threadId, Request $request): Response
         /** @var CommentInterface $comment */
         $comment = $this->commentRepository->createNew();
 
-        if ($parent = $request->get('parent')) {
+        /** @var null|int $parent */
+        $parent = $request->get('parent');
+        if ($parent) {
             $comment->setParent($this->commentRepository->findCommentById($parent));
         }
 
@@ -257,9 +266,12 @@ public function postCommentsAction(string $threadId, Request $request): Response
             return new Response(null, 400);
         }
 
+        /** @var CommentInterface $comment */
         $comment = $form->getData();
 
-        $this->commentManager->addComment($type, $entityId, $comment, $request->get('threadTitle'));
+        /** @var string $threadTitle */
+        $threadTitle = $request->get('threadTitle');
+        $this->commentManager->addComment($type, $entityId, $comment, $threadTitle);
         $this->entityManager->flush();
 
         if ($referrer = $request->query->get('referrer')) {
@@ -288,6 +300,7 @@ public function putCommentAction(string $threadId, string $commentId, Request $r
     {
         list($type, $entityId) = $this->getThreadIdParts($threadId);
 
+        /** @var string $message */
         $message = $request->request->get('message');
 
         /** @var Comment $comment */
@@ -317,7 +330,7 @@ public function putCommentAction(string $threadId, string $commentId, Request $r
     public function deleteCommentAction(string $threadId, string $commentId, Request $request): Response
     {
         /** @var Comment $comment */
-        $comment = $this->commentRepository->findCommentById(intval($commentId));
+        $comment = $this->commentRepository->findCommentById(\intval($commentId));
 
         $this->entityManager->remove($comment);
         $this->entityManager->flush();
@@ -333,9 +346,16 @@ public function deleteCommentAction(string $threadId, string $commentId, Request
         return new Response();
     }
 
+    /**
+     * @param null|mixed $data
+     * @param null|string $statusCode
+     * @param mixed[] $headers
+     *
+     * @return View
+     */
     protected function view($data = null, $statusCode = null, array $headers = [])
     {
-        $view = parent::view($data, $statusCode, $headers);
+        $view = parent::view($data, $statusCode ? (int) $statusCode : null, $headers);
 
         $context = new Context();
         $context->setGroups($this->commentSerializationGroups);
@@ -351,18 +371,21 @@ protected function view($data = null, $statusCode = null, array $headers = [])
      */
     private function getThreadIdParts(string $threadId): array
     {
-        $pos = strpos($threadId, '-');
+        $pos = \strpos($threadId, '-');
         if (false === $pos) {
             throw new \RuntimeException('Thread id is not valid.');
         }
 
-        return [substr($threadId, 0, $pos), substr($threadId, $pos + 1)];
+        return [\substr($threadId, 0, $pos), \substr($threadId, $pos + 1)];
     }
 
     private function getTemplate(string $type, string $templateType): string
     {
-        if (array_key_exists($type, $this->commentTypes)) {
-            return $this->commentTypes[$type]['templates'][$templateType];
+        if (\array_key_exists($type, $this->commentTypes)) {
+            /** @var array<string, string> $templates */
+            $templates = $this->commentTypes[$type]['templates'];
+
+            return $templates[$templateType];
         }
 
         return $this->commentDefaultTemplates[$templateType];
@@ -370,8 +393,11 @@ private function getTemplate(string $type, string $templateType): string
 
     private function getNestedCommentsEnabled(string $type): bool
     {
-        if (array_key_exists($type, $this->commentTypes)) {
-            return $this->commentTypes[$type]['nested_comments'];
+        if (\array_key_exists($type, $this->commentTypes)) {
+            /** @var bool $result */
+            $result = $this->commentTypes[$type]['nested_comments'];
+
+            return $result;
         }
 
         return $this->enableNestedCommentsDefault;
diff --git a/DependencyInjection/Configuration.php b/DependencyInjection/Configuration.php
index ca2faec2..d35765de 100644
--- a/DependencyInjection/Configuration.php
+++ b/DependencyInjection/Configuration.php
@@ -23,9 +23,6 @@
  */
 class Configuration implements ConfigurationInterface
 {
-    /**
-     * {@inheritdoc}
-     */
     public function getConfigTreeBuilder()
     {
         $treeBuilder = new TreeBuilder('sulu_comment');
diff --git a/DependencyInjection/SuluCommentExtension.php b/DependencyInjection/SuluCommentExtension.php
index 9135ab9c..cc65500c 100644
--- a/DependencyInjection/SuluCommentExtension.php
+++ b/DependencyInjection/SuluCommentExtension.php
@@ -25,10 +25,7 @@ class SuluCommentExtension extends Extension implements PrependExtensionInterfac
 {
     use PersistenceExtensionTrait;
 
-    /**
-     * {@inheritdoc}
-     */
-    public function prepend(ContainerBuilder $container)
+    public function prepend(ContainerBuilder $container): void
     {
         if ($container->hasExtension('jms_serializer')) {
             $container->prependExtensionConfig(
@@ -79,10 +76,7 @@ public function prepend(ContainerBuilder $container)
         }
     }
 
-    /**
-     * {@inheritdoc}
-     */
-    public function load(array $configs, ContainerBuilder $container)
+    public function load(array $configs, ContainerBuilder $container): void
     {
         $configuration = new Configuration();
         $config = $this->processConfiguration($configuration, $configs);
diff --git a/Entity/Comment.php b/Entity/Comment.php
index 0f1089f6..9e507e53 100644
--- a/Entity/Comment.php
+++ b/Entity/Comment.php
@@ -31,7 +31,7 @@ class Comment implements CommentInterface, AuditableInterface
     protected $state = self::STATE_PUBLISHED;
 
     /**
-     * @var string
+     * @var string|null
      */
     protected $message;
 
@@ -61,11 +61,11 @@ class Comment implements CommentInterface, AuditableInterface
     protected $parent;
 
     /**
-     * @var Collection|CommentInterface[]
+     * @var Collection<int, CommentInterface>|CommentInterface[]
      */
     protected $children;
 
-    public function __construct(int $state = self::STATE_PUBLISHED, ThreadInterface $thread = null)
+    public function __construct(int $state = self::STATE_PUBLISHED, ?ThreadInterface $thread = null)
     {
         $this->state = $state;
         $this->thread = $thread;
diff --git a/Entity/CommentInterface.php b/Entity/CommentInterface.php
index fd989de2..c59570b9 100644
--- a/Entity/CommentInterface.php
+++ b/Entity/CommentInterface.php
@@ -15,9 +15,9 @@
 
 interface CommentInterface
 {
-    const STATE_UNPUBLISHED = 0;
+    public const STATE_UNPUBLISHED = 0;
 
-    const STATE_PUBLISHED = 1;
+    public const STATE_PUBLISHED = 1;
 
     public function getId(): int;
 
@@ -39,12 +39,18 @@ public function setThread(ThreadInterface $thread): self;
 
     public function getParent(): ?CommentInterface;
 
-    public function setParent(CommentInterface $parent = null): CommentInterface;
+    public function setParent(?CommentInterface $parent = null): CommentInterface;
 
     public function getDepth(): int;
 
+    /**
+     * @return Collection<int, CommentInterface>
+     */
     public function getChildren(): Collection;
 
+    /**
+     * @return Collection<int, CommentInterface>
+     */
     public function getPublishedChildren(): Collection;
 
     public function getCreatorFullName(): string;
diff --git a/Entity/CommentRepository.php b/Entity/CommentRepository.php
index 38dde5f8..5af91a15 100644
--- a/Entity/CommentRepository.php
+++ b/Entity/CommentRepository.php
@@ -36,7 +36,10 @@ public function findComments(string $type, string $entityId, int $limit = 10, in
             $query->setFirstResult($offset);
         }
 
-        return $query->getResult();
+        /** @var CommentInterface[] $result */
+        $result = $query->getResult();
+
+        return $result;
     }
 
     public function findPublishedComments(
@@ -67,7 +70,10 @@ public function findPublishedComments(
             $query->setFirstResult($offset);
         }
 
-        return $query->getResult();
+        /** @var CommentInterface[] $result */
+        $result = $query->getResult();
+
+        return $result;
     }
 
     public function countPublishedComments(string $type, string $entityId): int
@@ -82,7 +88,10 @@ public function countPublishedComments(string $type, string $entityId): int
             ->setParameter('type', $type)
             ->setParameter('entityId', $entityId);
 
-        return $queryBuilder->getQuery()->getSingleScalarResult();
+        /** @var int $result */
+        $result = $queryBuilder->getQuery()->getSingleScalarResult();
+
+        return $result;
     }
 
     public function findCommentsByIds(array $ids): array
@@ -95,7 +104,10 @@ public function findCommentsByIds(array $ids): array
             ->setParameter('ids', $ids)
             ->getQuery();
 
-        return $query->getResult();
+        /** @var CommentInterface[] $result */
+        $result = $query->getResult();
+
+        return $result;
     }
 
     public function findCommentById(int $id): ?CommentInterface
@@ -109,7 +121,10 @@ public function findCommentById(int $id): ?CommentInterface
             ->getQuery();
 
         try {
-            return $query->getSingleResult();
+            /** @var CommentInterface $result */
+            $result = $query->getSingleResult();
+
+            return $result;
         } catch (NoResultException $e) {
             return null;
         }
@@ -125,8 +140,9 @@ public function delete(CommentInterface $comment): void
         $this->getEntityManager()->remove($comment);
     }
 
-    public function createNew()
+    public function createNew(): CommentInterface
     {
+        /** @var CommentInterface $className */
         $className = $this->getClassName();
 
         return new $className();
diff --git a/Entity/CommentRepositoryInterface.php b/Entity/CommentRepositoryInterface.php
index e2718ef5..48b368da 100644
--- a/Entity/CommentRepositoryInterface.php
+++ b/Entity/CommentRepositoryInterface.php
@@ -13,6 +13,9 @@
 
 use Sulu\Component\Persistence\Repository\RepositoryInterface;
 
+/**
+ * @extends RepositoryInterface<CommentInterface>
+ */
 interface CommentRepositoryInterface extends RepositoryInterface
 {
     /**
diff --git a/Entity/Thread.php b/Entity/Thread.php
index b9e40c27..79d4607a 100644
--- a/Entity/Thread.php
+++ b/Entity/Thread.php
@@ -47,7 +47,7 @@ class Thread implements ThreadInterface, AuditableInterface
     protected $commentCount = 0;
 
     /**
-     * @var Collection
+     * @var Collection<int, CommentInterface>
      */
     protected $comments;
 
@@ -71,7 +71,10 @@ class Thread implements ThreadInterface, AuditableInterface
      */
     protected $creator;
 
-    public function __construct(string $type, string $entityId, Collection $comments = null, int $commentCount = 0)
+    /**
+     * @param Collection<int, CommentInterface>|null $comments
+     */
+    public function __construct(string $type, string $entityId, ?Collection $comments = null, int $commentCount = 0)
     {
         $this->type = $type;
         $this->entityId = $entityId;
diff --git a/Entity/ThreadInterface.php b/Entity/ThreadInterface.php
index 775fc1d6..765a4c68 100644
--- a/Entity/ThreadInterface.php
+++ b/Entity/ThreadInterface.php
@@ -34,7 +34,7 @@ public function decreaseCommentCount(): self;
     public function setCommentCount(int $commentCount): self;
 
     /**
-     * @return CommentInterface[]|Collection
+     * @return CommentInterface[]|Collection<int, CommentInterface>
      */
     public function getComments(): Collection;
 
diff --git a/Entity/ThreadRepository.php b/Entity/ThreadRepository.php
index 2acc3da8..28bd49c2 100644
--- a/Entity/ThreadRepository.php
+++ b/Entity/ThreadRepository.php
@@ -13,6 +13,9 @@
 
 use Doctrine\ORM\EntityRepository;
 
+/**
+ * @extends EntityRepository<ThreadInterface>
+ */
 class ThreadRepository extends EntityRepository implements ThreadRepositoryInterface
 {
     public function createNew(string $type, string $entityId): ThreadInterface
diff --git a/EventSubscriber/CommentSerializationSubscriber.php b/EventSubscriber/CommentSerializationSubscriber.php
index 6e6e0ecc..357fad58 100644
--- a/EventSubscriber/CommentSerializationSubscriber.php
+++ b/EventSubscriber/CommentSerializationSubscriber.php
@@ -18,6 +18,7 @@
 use JMS\Serializer\Visitor\SerializationVisitorInterface;
 use Sulu\Bundle\CommentBundle\Entity\Comment;
 use Sulu\Bundle\MediaBundle\Media\Manager\MediaManagerInterface;
+use Sulu\Bundle\SecurityBundle\Entity\User;
 use Symfony\Component\HttpFoundation\RequestStack;
 
 class CommentSerializationSubscriber implements EventSubscriberInterface
@@ -38,7 +39,10 @@ public function __construct(MediaManagerInterface $mediaManager, RequestStack $r
         $this->requestStack = $requestStack;
     }
 
-    public static function getSubscribedEvents()
+    /**
+     * @return array<int, array<string, string>>
+     */
+    public static function getSubscribedEvents(): array
     {
         return [
             [
@@ -52,9 +56,9 @@ public static function getSubscribedEvents()
     public function onPostSerialize(ObjectEvent $event): void
     {
         $context = $event->getContext();
-
-        if (!$context->hasAttribute('groups')
-            || !in_array('commentWithAvatar', $context->getAttribute('groups'))) {
+        /** @var mixed[] $groups */
+        $groups = $context->hasAttribute('groups') ? $context->getAttribute('groups') : [];
+        if (!\in_array('commentWithAvatar', $groups)) {
             return;
         }
 
@@ -63,6 +67,7 @@ public function onPostSerialize(ObjectEvent $event): void
         if (!$comment instanceof Comment || !$creator = $comment->getCreator()) {
             return;
         }
+        /** @var User $creator */
 
         /** @var SerializationVisitorInterface $visitor */
         $visitor = $event->getVisitor();
diff --git a/Events/Events.php b/Events/Events.php
index 1243dfe1..a1c922e4 100644
--- a/Events/Events.php
+++ b/Events/Events.php
@@ -13,25 +13,25 @@
 
 final class Events
 {
-    const PRE_PERSIST_EVENT = 'sulu_comment.pre_persist';
+    public const PRE_PERSIST_EVENT = 'sulu_comment.pre_persist';
 
-    const POST_PERSIST_EVENT = 'sulu_comment.post_persist';
+    public const POST_PERSIST_EVENT = 'sulu_comment.post_persist';
 
-    const PRE_DELETE_EVENT = 'sulu_comment.pre_delete';
+    public const PRE_DELETE_EVENT = 'sulu_comment.pre_delete';
 
-    const POST_DELETE_EVENT = 'sulu_comment.post_delete';
+    public const POST_DELETE_EVENT = 'sulu_comment.post_delete';
 
-    const PRE_UPDATE_EVENT = 'sulu_comment.pre_update';
+    public const PRE_UPDATE_EVENT = 'sulu_comment.pre_update';
 
-    const PUBLISH_EVENT = 'sulu_comment.publish';
+    public const PUBLISH_EVENT = 'sulu_comment.publish';
 
-    const UNPUBLISH_EVENT = 'sulu_comment.unpublish';
+    public const UNPUBLISH_EVENT = 'sulu_comment.unpublish';
 
-    const THREAD_PRE_UPDATE_EVENT = 'sulu_comment.thread.pre_update';
+    public const THREAD_PRE_UPDATE_EVENT = 'sulu_comment.thread.pre_update';
 
-    const THREAD_PRE_DELETE_EVENT = 'sulu_comment.thread.pre_delete';
+    public const THREAD_PRE_DELETE_EVENT = 'sulu_comment.thread.pre_delete';
 
-    const THREAD_POST_DELETE_EVENT = 'sulu_comment.thread.post_delete';
+    public const THREAD_POST_DELETE_EVENT = 'sulu_comment.thread.post_delete';
 
     /**
      * Private constructor.
diff --git a/Form/Type/CommentType.php b/Form/Type/CommentType.php
index a493496a..a54d9faa 100644
--- a/Form/Type/CommentType.php
+++ b/Form/Type/CommentType.php
@@ -31,7 +31,7 @@ public function __construct(UrlGeneratorInterface $router)
         $this->router = $router;
     }
 
-    public function buildForm(FormBuilderInterface $builder, array $options)
+    public function buildForm(FormBuilderInterface $builder, array $options): void
     {
         $attributes = ['threadId' => $options['threadId']];
         if ($options['referrer']) {
@@ -47,7 +47,7 @@ public function buildForm(FormBuilderInterface $builder, array $options)
         $builder->add('submit', SubmitType::class);
     }
 
-    public function configureOptions(OptionsResolver $resolver)
+    public function configureOptions(OptionsResolver $resolver): void
     {
         $resolver->setRequired('threadId');
         $resolver->setDefault('referrer', null);
diff --git a/Manager/CommentManager.php b/Manager/CommentManager.php
index 56e01d20..65c5f9c6 100644
--- a/Manager/CommentManager.php
+++ b/Manager/CommentManager.php
@@ -74,7 +74,7 @@ public function addComment(
         string $type,
         string $entityId,
         CommentInterface $comment,
-        string $threadTitle = null
+        ?string $threadTitle = null
     ): ThreadInterface {
         $thread = $this->threadRepository->findThread($type, $entityId);
         if (!$thread) {
@@ -106,7 +106,7 @@ public function update(CommentInterface $comment): CommentInterface
 
     public function delete(array $ids): void
     {
-        if (!is_array($ids)) {
+        if (!\is_array($ids)) {
             $ids = [$ids];
         }
 
@@ -125,7 +125,7 @@ public function updateThread(ThreadInterface $thread): ThreadInterface
 
     public function deleteThreads(array $ids): void
     {
-        if (!is_array($ids)) {
+        if (!\is_array($ids)) {
             $ids = [$ids];
         }
 
diff --git a/SuluCommentBundle.php b/SuluCommentBundle.php
index 86c0a14d..ae2bef2f 100644
--- a/SuluCommentBundle.php
+++ b/SuluCommentBundle.php
@@ -24,10 +24,7 @@ class SuluCommentBundle extends Bundle
 {
     use PersistenceBundleTrait;
 
-    /**
-     * {@inheritdoc}
-     */
-    public function build(ContainerBuilder $container)
+    public function build(ContainerBuilder $container): void
     {
         $this->buildPersistence(
             [
diff --git a/Tests/Application/.env b/Tests/Application/.env
index 01152b1b..b51d3365 100644
--- a/Tests/Application/.env
+++ b/Tests/Application/.env
@@ -1,2 +1,2 @@
 APP_ENV=test
-DATABASE_URL=mysql://root@localhost:3306/su_comment_test
+DATABASE_URL=mysql://root@127.0.0.1:3306/su_comment_test
diff --git a/Tests/Application/Kernel.php b/Tests/Application/Kernel.php
index 40f9b673..72f051cc 100644
--- a/Tests/Application/Kernel.php
+++ b/Tests/Application/Kernel.php
@@ -20,7 +20,7 @@
 
 class Kernel extends SuluTestKernel
 {
-    public function registerBundles()
+    public function registerBundles(): iterable
     {
         $bundles = parent::registerBundles();
         $bundles[] = new SuluCommentBundle();
@@ -38,9 +38,15 @@ public function registerContainerConfiguration(LoaderInterface $loader)
 
         $context = $this->getContext();
         $loader->load(__DIR__ . '/config/config_' . $context . '.yml');
+
+        if (\version_compare(Kernel::VERSION, '6.0.0', '>=')) {
+            $loader->load(__DIR__ . '/config/security-6.yml');
+        } else {
+            $loader->load(__DIR__ . '/config/security-5-4.yml');
+        }
     }
 
-    protected function getKernelParameters()
+    protected function getKernelParameters(): array
     {
         $parameters = parent::getKernelParameters();
 
diff --git a/Tests/Application/bin/console.php b/Tests/Application/bin/console.php
index 5c7b283d..344c61b8 100644
--- a/Tests/Application/bin/console.php
+++ b/Tests/Application/bin/console.php
@@ -13,9 +13,9 @@
 
 // if you don't want to setup permissions the proper way, just uncomment the following PHP line
 // read http://symfony.com/doc/current/book/installation.html#configuration-and-setup for more information
-//umask(0000);
+// umask(0000);
 
-set_time_limit(0);
+\set_time_limit(0);
 
 require_once __DIR__ . '/../config/bootstrap.php';
 
@@ -25,12 +25,12 @@
 use Symfony\Component\ErrorHandler\Debug;
 
 $input = new ArgvInput();
-$env = $input->getParameterOption(['--env', '-e'], getenv('SYMFONY_ENV') ?: 'dev');
-$debug = '0' !== getenv('SYMFONY_DEBUG') && !$input->hasParameterOption(['--no-debug', '']) && 'prod' !== $env;
+$env = $input->getParameterOption(['--env', '-e'], \getenv('SYMFONY_ENV') ?: 'dev');
+$debug = '0' !== \getenv('SYMFONY_DEBUG') && !$input->hasParameterOption(['--no-debug', '']) && 'prod' !== $env;
 
 if ($debug) {
     // Clean up when sf 4.3 support is removed
-    if (class_exists(Debug::class)) {
+    if (\class_exists(Debug::class)) {
         Debug::enable();
     } else {
         \Symfony\Component\Debug\Debug::enable();
diff --git a/Tests/Application/config/bootstrap.php b/Tests/Application/config/bootstrap.php
index 3bc0a8fd..7314acf9 100644
--- a/Tests/Application/config/bootstrap.php
+++ b/Tests/Application/config/bootstrap.php
@@ -15,7 +15,7 @@
 
 $file = __DIR__ . '/../../../vendor/autoload.php';
 
-if (!file_exists($file)) {
+if (!\file_exists($file)) {
     throw new RuntimeException('Install dependencies to run test suite.');
 }
 
@@ -23,17 +23,17 @@
 
 // Load cached env vars if the .env.local.php file exists
 // Run "composer dump-env prod" to create it (requires symfony/flex >=1.2)
-if (is_array($env = @include dirname(__DIR__) . '/.env.local.php')) {
+if (\is_array($env = @include \dirname(__DIR__) . '/.env.local.php')) {
     $_SERVER += $env;
     $_ENV += $env;
-} elseif (!class_exists(Dotenv::class)) {
+} elseif (!\class_exists(Dotenv::class)) {
     throw new RuntimeException('Please run "composer require symfony/dotenv" to load the ".env" files configuring the application.');
 } else {
-    $path = dirname(__DIR__) . '/.env';
+    $path = \dirname(__DIR__) . '/.env';
     $dotenv = new Dotenv();
     $dotenv->loadEnv($path);
 }
 
 $_SERVER['APP_ENV'] = $_ENV['APP_ENV'] = ($_SERVER['APP_ENV'] ?? $_ENV['APP_ENV'] ?? null) ?: 'dev';
 $_SERVER['APP_DEBUG'] = $_SERVER['APP_DEBUG'] ?? $_ENV['APP_DEBUG'] ?? 'prod' !== $_SERVER['APP_ENV'];
-$_SERVER['APP_DEBUG'] = $_ENV['APP_DEBUG'] = (int) $_SERVER['APP_DEBUG'] || filter_var($_SERVER['APP_DEBUG'], FILTER_VALIDATE_BOOLEAN) ? '1' : '0';
+$_SERVER['APP_DEBUG'] = $_ENV['APP_DEBUG'] = (int) $_SERVER['APP_DEBUG'] || \filter_var($_SERVER['APP_DEBUG'], \FILTER_VALIDATE_BOOLEAN) ? '1' : '0';
diff --git a/Tests/Application/config/config_admin.yml b/Tests/Application/config/config_admin.yml
index c77da5a5..49b8adfe 100644
--- a/Tests/Application/config/config_admin.yml
+++ b/Tests/Application/config/config_admin.yml
@@ -3,7 +3,7 @@ parameters:
     database.url: '%env(resolve:DATABASE_URL)%'
 
 framework:
-    router: { resource: "%kernel.root_dir%/config/routing_admin.yml" }
+    router: { resource: "%kernel.project_dir%/config/routing_admin.yml" }
 
 doctrine:
     orm:
diff --git a/Tests/Application/config/config_website.yml b/Tests/Application/config/config_website.yml
index 81a150d6..e2996903 100644
--- a/Tests/Application/config/config_website.yml
+++ b/Tests/Application/config/config_website.yml
@@ -3,15 +3,12 @@ parameters:
     database.url: '%env(resolve:DATABASE_URL)%'
 
 framework:
-    router: { resource: "%kernel.root_dir%/config/routing_website.yml" }
+    router: { resource: "%kernel.project_dir%/config/routing_website.yml" }
 
 security:
     access_decision_manager:
         strategy: affirmative
 
-    encoders:
-        Sulu\Bundle\SecurityBundle\Entity\User: plaintext
-
     providers:
         testprovider:
             id: test_user_provider
@@ -22,7 +19,6 @@ security:
     firewalls:
         test:
             http_basic: ~
-            anonymous: ~
 
 sulu_test:
     enable_test_user_provider: true
diff --git a/Tests/Application/config/security-5-4.yml b/Tests/Application/config/security-5-4.yml
new file mode 100644
index 00000000..95e396ba
--- /dev/null
+++ b/Tests/Application/config/security-5-4.yml
@@ -0,0 +1,3 @@
+security:
+    encoders:
+        Sulu\Bundle\SecurityBundle\Entity\User: plaintext
diff --git a/Tests/Application/config/security-6.yml b/Tests/Application/config/security-6.yml
new file mode 100644
index 00000000..37b120e7
--- /dev/null
+++ b/Tests/Application/config/security-6.yml
@@ -0,0 +1,3 @@
+security:
+    password_hashers:
+        Sulu\Bundle\SecurityBundle\Entity\User: plaintext
diff --git a/Tests/Functional/Controller/CommentControllerTest.php b/Tests/Functional/Controller/CommentControllerTest.php
index 3354f091..98fd2337 100644
--- a/Tests/Functional/Controller/CommentControllerTest.php
+++ b/Tests/Functional/Controller/CommentControllerTest.php
@@ -18,6 +18,7 @@
 use Sulu\Bundle\CommentBundle\Entity\Thread;
 use Sulu\Bundle\CommentBundle\Entity\ThreadInterface;
 use Sulu\Bundle\TestBundle\Testing\SuluTestCase;
+use Symfony\Bundle\FrameworkBundle\KernelBrowser;
 
 class CommentControllerTest extends SuluTestCase
 {
@@ -26,8 +27,14 @@ class CommentControllerTest extends SuluTestCase
      */
     private $entityManager;
 
+    /**
+     * @var KernelBrowser
+     */
+    private $client;
+
     protected function setUp(): void
     {
+        $this->client = $this->createAuthenticatedClient();
         $this->entityManager = $this->getContainer()->get('doctrine.orm.entity_manager');
 
         $this->purgeDatabase();
@@ -40,11 +47,10 @@ public function testGet()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('GET', '/api/comments/' . $comment->getId());
+        $this->client->request('GET', '/api/comments/' . $comment->getId());
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
-        $data = json_decode($client->getResponse()->getContent(), true);
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
+        $data = \json_decode($this->client->getResponse()->getContent(), true);
 
         $this->assertEquals($comment->getId(), $data['id']);
         $this->assertEquals($comment->getMessage(), $data['message']);
@@ -59,11 +65,10 @@ public function testCGet()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('GET', '/api/comments');
+        $this->client->request('GET', '/api/comments');
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
-        $data = json_decode($client->getResponse()->getContent(), true);
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
+        $data = \json_decode($this->client->getResponse()->getContent(), true);
 
         $this->assertCount(3, $data['_embedded']['comments']);
     }
@@ -78,11 +83,10 @@ public function testCGetFilter()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('GET', '/api/comments?state=' . CommentInterface::STATE_UNPUBLISHED);
+        $this->client->request('GET', '/api/comments?state=' . CommentInterface::STATE_UNPUBLISHED);
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
-        $data = json_decode($client->getResponse()->getContent(), true);
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
+        $data = \json_decode($this->client->getResponse()->getContent(), true);
 
         $this->assertCount(1, $data['_embedded']['comments']);
     }
@@ -99,11 +103,10 @@ public function testCGetTypeFilter()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('GET', '/api/comments?threadType=test-1,test-2');
+        $this->client->request('GET', '/api/comments?threadType=test-1,test-2');
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
-        $data = json_decode($client->getResponse()->getContent(), true);
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
+        $data = \json_decode($this->client->getResponse()->getContent(), true);
 
         $this->assertCount(2, $data['_embedded']['comments']);
     }
@@ -115,11 +118,10 @@ public function testPut()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('PUT', '/api/comments/' . $comment->getId(), ['message' => 'My new Message']);
+        $this->client->request('PUT', '/api/comments/' . $comment->getId(), ['message' => 'My new Message']);
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
-        $data = json_decode($client->getResponse()->getContent(), true);
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
+        $data = \json_decode($this->client->getResponse()->getContent(), true);
 
         $this->assertEquals($comment->getId(), $data['id']);
         $this->assertEquals('My new Message', $data['message']);
@@ -132,10 +134,9 @@ public function testDelete()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('DELETE', '/api/comments/' . $comment->getId());
+        $this->client->request('DELETE', '/api/comments/' . $comment->getId());
 
-        $this->assertHttpStatusCode(204, $client->getResponse());
+        $this->assertHttpStatusCode(204, $this->client->getResponse());
 
         $this->assertNull($this->entityManager->find(CommentInterface::class, $comment->getId()));
     }
@@ -151,12 +152,11 @@ public function testCDelete()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request(
+        $this->client->request(
             'DELETE',
-            '/api/comments?ids=' . implode(
+            '/api/comments?ids=' . \implode(
                 ',',
-                array_map(
+                \array_map(
                     function(CommentInterface $comment) {
                         return $comment->getId();
                     },
@@ -165,7 +165,7 @@ function(CommentInterface $comment) {
             )
         );
 
-        $this->assertHttpStatusCode(204, $client->getResponse());
+        $this->assertHttpStatusCode(204, $this->client->getResponse());
 
         foreach ([$comments[0], $comments[1]] as $comment) {
             $this->assertNull($this->entityManager->find(CommentInterface::class, $comment->getId()));
@@ -183,9 +183,8 @@ public function testPublish()
 
         $this->assertFalse($comment->isPublished());
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('POST', '/api/comments/' . $comment->getId() . '?action=publish');
-        $this->assertHttpStatusCode(200, $client->getResponse());
+        $this->client->request('POST', '/api/comments/' . $comment->getId() . '?action=publish');
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
 
         $result = $this->entityManager->find(CommentInterface::class, $comment->getId());
         $this->assertTrue($result->isPublished());
@@ -200,9 +199,8 @@ public function testUnpublish()
 
         $this->assertTrue($comment->isPublished());
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('POST', '/api/comments/' . $comment->getId() . '?action=unpublish');
-        $this->assertHttpStatusCode(200, $client->getResponse());
+        $this->client->request('POST', '/api/comments/' . $comment->getId() . '?action=unpublish');
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
 
         $result = $this->entityManager->find(CommentInterface::class, $comment->getId());
         $this->assertFalse($result->isPublished());
diff --git a/Tests/Functional/Controller/ThreadControllerTest.php b/Tests/Functional/Controller/ThreadControllerTest.php
index 18d96226..405beeac 100644
--- a/Tests/Functional/Controller/ThreadControllerTest.php
+++ b/Tests/Functional/Controller/ThreadControllerTest.php
@@ -16,6 +16,7 @@
 use Sulu\Bundle\CommentBundle\Entity\Thread;
 use Sulu\Bundle\CommentBundle\Entity\ThreadInterface;
 use Sulu\Bundle\TestBundle\Testing\SuluTestCase;
+use Symfony\Bundle\FrameworkBundle\KernelBrowser;
 
 class ThreadControllerTest extends SuluTestCase
 {
@@ -24,8 +25,14 @@ class ThreadControllerTest extends SuluTestCase
      */
     private $entityManager;
 
+    /**
+     * @var KernelBrowser
+     */
+    private $client;
+
     protected function setUp(): void
     {
+        $this->client = $this->createAuthenticatedClient();
         $this->entityManager = $this->getContainer()->get('doctrine.orm.entity_manager');
 
         $this->purgeDatabase();
@@ -37,11 +44,10 @@ public function testGet()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('GET', '/api/threads/' . $thread->getId());
+        $this->client->request('GET', '/api/threads/' . $thread->getId());
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
-        $data = json_decode($client->getResponse()->getContent(), true);
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
+        $data = \json_decode($this->client->getResponse()->getContent(), true);
 
         $this->assertEquals($thread->getId(), $data['id']);
         $this->assertEquals($thread->getTitle(), $data['title']);
@@ -56,11 +62,10 @@ public function testCGetFilter()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('GET', '/api/threads?type=page');
+        $this->client->request('GET', '/api/threads?type=page');
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
-        $data = json_decode($client->getResponse()->getContent(), true);
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
+        $data = \json_decode($this->client->getResponse()->getContent(), true);
 
         $this->assertCount(2, $data['_embedded']['threads']);
     }
@@ -71,11 +76,10 @@ public function testPut()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('PUT', '/api/threads/' . $thread->getId(), ['title' => 'My new Title']);
+        $this->client->request('PUT', '/api/threads/' . $thread->getId(), ['title' => 'My new Title']);
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
-        $data = json_decode($client->getResponse()->getContent(), true);
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
+        $data = \json_decode($this->client->getResponse()->getContent(), true);
 
         $this->assertEquals($thread->getId(), $data['id']);
         $this->assertEquals('My new Title', $data['title']);
@@ -87,10 +91,9 @@ public function testDelete()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('DELETE', '/api/threads/' . $thread->getId());
+        $this->client->request('DELETE', '/api/threads/' . $thread->getId());
 
-        $this->assertHttpStatusCode(204, $client->getResponse());
+        $this->assertHttpStatusCode(204, $this->client->getResponse());
 
         $this->assertNull($this->entityManager->find(ThreadInterface::class, $thread->getId()));
     }
@@ -105,12 +108,11 @@ public function testCDelete()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request(
+        $this->client->request(
             'DELETE',
-            '/api/threads?ids=' . implode(
+            '/api/threads?ids=' . \implode(
                 ',',
-                array_map(
+                \array_map(
                     function(ThreadInterface $thread) {
                         return $thread->getId();
                     },
@@ -119,7 +121,7 @@ function(ThreadInterface $thread) {
             )
         );
 
-        $this->assertHttpStatusCode(204, $client->getResponse());
+        $this->assertHttpStatusCode(204, $this->client->getResponse());
 
         foreach ([$threads[0], $threads[1]] as $comment) {
             $this->assertNull($this->entityManager->find(ThreadInterface::class, $comment->getId()));
@@ -139,14 +141,13 @@ public function testCGet()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('GET', '/api/threads?fields=id,title');
+        $this->client->request('GET', '/api/threads?fields=id,title');
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
 
-        $result = json_decode($client->getResponse()->getContent(), true);
+        $result = \json_decode($this->client->getResponse()->getContent(), true);
         $result = $result['_embedded']['threads'];
-        for ($i = 0, $length = count($threads); $i < $length; ++$i) {
+        for ($i = 0, $length = \count($threads); $i < $length; ++$i) {
             $this->assertEquals($threads[$i]->getId(), $result[$i]['id']);
             $this->assertEquals($threads[$i]->getTitle(), $result[$i]['title']);
         }
@@ -163,16 +164,15 @@ public function testCGetTypes()
         $this->entityManager->flush();
         $this->entityManager->clear();
 
-        $client = $this->createAuthenticatedClient();
-        $client->request('GET', '/api/threads?fields=id,title&types=Test1,Test3');
+        $this->client->request('GET', '/api/threads?fields=id,title&types=Test1,Test3');
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
 
-        $result = json_decode($client->getResponse()->getContent(), true);
+        $result = \json_decode($this->client->getResponse()->getContent(), true);
         $result = $result['_embedded']['threads'];
 
         $expected = [$threads[0], $threads[2]];
-        for ($i = 0, $length = count($expected); $i < $length; ++$i) {
+        for ($i = 0, $length = \count($expected); $i < $length; ++$i) {
             $this->assertEquals($expected[$i]->getId(), $result[$i]['id']);
             $this->assertEquals($expected[$i]->getTitle(), $result[$i]['title']);
         }
diff --git a/Tests/Functional/Controller/WebsiteCommentControllerTest.php b/Tests/Functional/Controller/WebsiteCommentControllerTest.php
index e5ef214d..a205e5df 100644
--- a/Tests/Functional/Controller/WebsiteCommentControllerTest.php
+++ b/Tests/Functional/Controller/WebsiteCommentControllerTest.php
@@ -14,6 +14,7 @@
 use Sulu\Bundle\CommentBundle\Entity\CommentInterface;
 use Sulu\Bundle\CommentBundle\Entity\ThreadInterface;
 use Sulu\Bundle\TestBundle\Testing\SuluTestCase;
+use Symfony\Bundle\FrameworkBundle\KernelBrowser;
 use Symfony\Component\HttpFoundation\RedirectResponse;
 
 /**
@@ -21,8 +22,14 @@
  */
 class WebsiteCommentControllerTest extends SuluTestCase
 {
+    /**
+     * @var KernelBrowser
+     */
+    private $client;
+
     protected function setUp(): void
     {
+        $this->client = $this->createAuthenticatedWebsiteClient();
         $this->purgeDatabase();
     }
 
@@ -43,16 +50,15 @@ public function testPostComment(
         $message = 'Sulu is awesome',
         $threadTitle = 'Test Thread'
     ) {
-        $client = $this->createWebsiteClient();
-        $client->request(
+        $this->client->request(
             'POST',
             '_api/threads/' . $type . '-' . $entityId . '/comments.json',
             ['message' => $message, 'threadTitle' => $threadTitle]
         );
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
 
-        $response = json_decode($client->getResponse()->getContent(), true);
+        $response = \json_decode($this->client->getResponse()->getContent(), true);
 
         $this->assertEquals(CommentInterface::STATE_PUBLISHED, $response['state']);
         $this->assertEquals($message, $response['message']);
@@ -82,16 +88,15 @@ public function testPostCommentWithParent(
         /** @var CommentInterface $parent */
         $parent = $thread->getComments()->first();
 
-        $client = $this->createWebsiteClient();
-        $client->request(
+        $this->client->request(
             'POST',
             '_api/threads/' . $type . '-' . $entityId . '/comments.json?parent=' . $parent->getId(),
             ['message' => $message, 'threadTitle' => $threadTitle]
         );
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
 
-        $response = json_decode($client->getResponse()->getContent(), true);
+        $response = \json_decode($this->client->getResponse()->getContent(), true);
 
         $this->assertEquals(CommentInterface::STATE_PUBLISHED, $response['state']);
         $this->assertEquals($message, $response['message']);
@@ -119,15 +124,14 @@ public function testPostCommentWithReferrer(
         $message = 'Sulu is awesome',
         $threadTitle = 'Test Thread'
     ) {
-        $client = $this->createWebsiteClient();
-        $client->request(
+        $this->client->request(
             'POST',
             '_api/threads/' . $type . '-' . $entityId . '/comments?referrer=https://sulu.io',
             ['message' => $message, 'threadTitle' => $threadTitle]
         );
 
         /** @var RedirectResponse $response */
-        $response = $client->getResponse();
+        $response = $this->client->getResponse();
         $this->assertHttpStatusCode(302, $response);
         $this->assertInstanceOf(RedirectResponse::class, $response);
         $this->assertEquals('https://sulu.io', $response->getTargetUrl());
@@ -154,14 +158,13 @@ public function providePostAuditableData()
      */
     public function testPostAuditable($field, $type = 'blog', $entityId = '1')
     {
-        $client = $this->createWebsiteClient();
-        $client->request(
+        $this->client->request(
             'POST',
             '_api/threads/' . $type . '-' . $entityId . '/comments.json',
             ['message' => 'Sulu is awesome', 'threadTitle' => 'Test Thread', $field => 1]
         );
 
-        $this->assertHttpStatusCode(400, $client->getResponse());
+        $this->assertHttpStatusCode(400, $this->client->getResponse());
     }
 
     public function testPostCommentMultiple($type = 'blog', $entityId = '1')
@@ -187,14 +190,13 @@ public function testPutComment($type = 'blog', $entityId = '1')
         $thread = $this->postComment($type, $entityId);
         $comment = $thread->getComments()->first();
 
-        $client = $this->createWebsiteClient();
-        $client->request(
+        $this->client->request(
             'POST',
             '_api/threads/' . $type . '-' . $entityId . '/comments/' . $comment->getId() . '.json',
             ['message' => 'New message']
         );
 
-        $response = json_decode($client->getResponse()->getContent(), true);
+        $response = \json_decode($this->client->getResponse()->getContent(), true);
         $this->assertEquals('New message', $response['message']);
 
         $this->getEntityManager()->clear();
@@ -208,15 +210,14 @@ public function testPutCommentWithReferrer($type = 'blog', $entityId = '1')
         $thread = $this->postComment($type, $entityId);
         $comment = $thread->getComments()->first();
 
-        $client = $this->createWebsiteClient();
-        $client->request(
+        $this->client->request(
             'POST',
             '_api/threads/' . $type . '-' . $entityId . '/comments/' . $comment->getId() . '?referrer=https://sulu.io',
             ['message' => 'New message']
         );
 
         /** @var RedirectResponse $response */
-        $response = $client->getResponse();
+        $response = $this->client->getResponse();
         $this->assertHttpStatusCode(302, $response);
         $this->assertInstanceOf(RedirectResponse::class, $response);
         $this->assertEquals('https://sulu.io', $response->getTargetUrl());
@@ -232,14 +233,13 @@ public function testDeleteComment($type = 'blog', $entityId = '1')
         $thread = $this->postComment($type, $entityId);
         $comment = $thread->getComments()->first();
 
-        $client = $this->createWebsiteClient();
-        $client->request(
+        $this->client->request(
             'DELETE',
             '_api/threads/' . $type . '-' . $entityId . '/comments/' . $comment->getId() . '.json'
         );
 
         /* Todo: Check if this is correct. */
-        $response = json_decode($client->getResponse()->getContent(), true);
+        $response = \json_decode($this->client->getResponse()->getContent(), true);
         $this->assertEquals('', $response);
 
         $this->getEntityManager()->clear();
@@ -253,14 +253,13 @@ public function testDeleteCommitWithReferrer($type = 'blog', $entityId = '1')
         $thread = $this->postComment($type, $entityId);
         $comment = $thread->getComments()->first();
 
-        $client = $this->createWebsiteClient();
-        $client->request(
+        $this->client->request(
             'DELETE',
             '_api/threads/' . $type . '-' . $entityId . '/comments/' . $comment->getId() . '?referrer=https://sulu.io'
         );
 
         /** @var RedirectResponse $response */
-        $response = $client->getResponse();
+        $response = $this->client->getResponse();
         $this->assertHttpStatusCode(302, $response);
         $this->assertInstanceOf(RedirectResponse::class, $response);
         $this->assertEquals('https://sulu.io', $response->getTargetUrl());
@@ -274,19 +273,18 @@ public function testDeleteCommitWithReferrer($type = 'blog', $entityId = '1')
     public function testGetComments($type = 'blog', $entityId = '1')
     {
         $this->postComment($type, $entityId);
-        sleep(1);
+        \sleep(1);
         $this->postComment($type, $entityId, 'My new Comment');
         $this->postComment('article', '123-123-123');
 
-        $client = $this->createWebsiteClient();
-        $client->request(
+        $this->client->request(
             'GET',
             '_api/threads/' . $type . '-' . $entityId . '/comments.json'
         );
 
-        $this->assertHttpStatusCode(200, $client->getResponse());
+        $this->assertHttpStatusCode(200, $this->client->getResponse());
 
-        $response = json_decode($client->getResponse()->getContent(), true);
+        $response = \json_decode($this->client->getResponse()->getContent(), true);
         $this->assertCount(2, $response);
         $this->assertEquals(CommentInterface::STATE_PUBLISHED, $response[0]['state']);
         $this->assertEquals('My new Comment', $response[0]['message']);
@@ -300,8 +298,7 @@ private function postComment(
         $message = 'Sulu is awesome',
         $threadTitle = 'Test Thread'
     ) {
-        $client = $this->createWebsiteClient();
-        $client->request(
+        $this->client->request(
             'POST',
             '_api/threads/' . $type . '-' . $entityId . '/comments.json',
             ['message' => $message, 'threadTitle' => $threadTitle]
@@ -309,6 +306,9 @@ private function postComment(
 
         $thread = $this->getContainer()->get('sulu.repository.thread')->findThread($type, $entityId);
 
+        // client has to be restarted for the next request to work
+        $this->client->restart();
+
         return $thread;
     }
 }
diff --git a/Tests/Functional/EventSubscriber/CommentSerializationSubscriberTest.php b/Tests/Functional/EventSubscriber/CommentSerializationSubscriberTest.php
index afc04428..a34463f0 100644
--- a/Tests/Functional/EventSubscriber/CommentSerializationSubscriberTest.php
+++ b/Tests/Functional/EventSubscriber/CommentSerializationSubscriberTest.php
@@ -27,7 +27,7 @@ public function testSerializeWithoutGroup()
         $comment->setMessage('test-message');
 
         $jsonResult = self::getContainer()->get('jms_serializer')->serialize($comment, 'json');
-        $arrayResult = json_decode($jsonResult, true);
+        $arrayResult = \json_decode($jsonResult, true);
 
         $this->assertTrue($arrayResult['published']);
         $this->assertSame('test-message', $arrayResult['message']);
@@ -41,7 +41,7 @@ public function testSerializeWithoutCreator()
 
         $context = SerializationContext::create()->setGroups(['Default', 'commentWithAvatar']);
         $jsonResult = self::getContainer()->get('jms_serializer')->serialize($comment, 'json', $context);
-        $arrayResult = json_decode($jsonResult, true);
+        $arrayResult = \json_decode($jsonResult, true);
 
         $this->assertTrue($arrayResult['published']);
         $this->assertSame('test-message', $arrayResult['message']);
@@ -57,7 +57,7 @@ public function testSerializeWithCreator()
 
         $context = SerializationContext::create()->setGroups(['Default', 'commentWithAvatar']);
         $jsonResult = self::getContainer()->get('jms_serializer')->serialize($comment, 'json', $context);
-        $arrayResult = json_decode($jsonResult, true);
+        $arrayResult = \json_decode($jsonResult, true);
 
         $this->assertTrue($arrayResult['published']);
         $this->assertSame('test-message', $arrayResult['message']);
diff --git a/Tests/Unit/Manager/CommentManagerTest.php b/Tests/Unit/Manager/CommentManagerTest.php
index 805ed926..00b2db33 100644
--- a/Tests/Unit/Manager/CommentManagerTest.php
+++ b/Tests/Unit/Manager/CommentManagerTest.php
@@ -96,7 +96,7 @@ public function testAddComment($type = 'article', $entityId = '123-123-123')
         $this->dispatcher->dispatch(Argument::type(CommentEvent::class), Events::PRE_PERSIST_EVENT)
             ->shouldBeCalledTimes(1)
             ->will(
-                function() use ($commentRepository, $comment, $dispatcher, $thread) {
+                function($args) use ($commentRepository, $comment, $dispatcher, $thread) {
                     $thread->addComment($comment->reveal())->willReturn($thread->reveal());
                     $commentRepository->persist($comment->reveal())
                         ->shouldBeCalledTimes(1)
@@ -108,6 +108,9 @@ function() use ($dispatcher) {
                                 )->shouldBeCalledTimes(1);
                             }
                         );
+
+                    // return the event
+                    return $args[0];
                 }
             );
 
@@ -130,7 +133,7 @@ public function testAddCommentWithThreadTitle($type = 'article', $entityId = '12
         $this->dispatcher->dispatch(Argument::type(CommentEvent::class), Events::PRE_PERSIST_EVENT)
             ->shouldBeCalledTimes(1)
             ->will(
-                function() use ($commentRepository, $comment, $dispatcher, $thread) {
+                function($args) use ($commentRepository, $comment, $dispatcher, $thread) {
                     $thread->addComment($comment->reveal())->willReturn($thread->reveal());
                     $commentRepository->persist($comment->reveal())
                         ->shouldBeCalledTimes(1)
@@ -142,6 +145,9 @@ function() use ($dispatcher) {
                                 )->shouldBeCalledTimes(1);
                             }
                         );
+
+                    // return the event
+                    return $args[0];
                 }
             );
 
@@ -164,7 +170,8 @@ function(CommentEvent $event) use ($comment) {
                 }
             ),
             Events::PRE_UPDATE_EVENT
-        )->shouldBeCalled();
+        )->shouldBeCalled()
+        ->willReturn(new CommentEvent('', '', $this->comment->reveal(), $this->thread->reveal()));
 
         $this->assertEquals($comment->reveal(), $this->commentManager->update($comment->reveal()));
         $this->commentEventCollector->dispatch(); // simulate flush of the comments
@@ -181,7 +188,8 @@ function(ThreadEvent $event) use ($thread) {
                 }
             ),
             Events::THREAD_PRE_UPDATE_EVENT
-        )->shouldBeCalled();
+        )->shouldBeCalled()
+        ->willReturn(new ThreadEvent($this->thread->reveal()));
 
         $this->assertEquals($thread->reveal(), $this->commentManager->updateThread($thread->reveal()));
         $this->commentEventCollector->dispatch(); // simulate flush of the comments
@@ -214,7 +222,7 @@ function(CommentEvent $event) use ($comment) {
                 ),
                 Events::PRE_DELETE_EVENT
             )->will(
-                function() use ($comment, $dispatcher) {
+                function($args) use ($comment, $dispatcher) {
                     $dispatcher->dispatch(
                         Argument::that(
                             function(CommentEvent $event) use ($comment) {
@@ -223,6 +231,9 @@ function(CommentEvent $event) use ($comment) {
                         ),
                         Events::POST_DELETE_EVENT
                     )->shouldBeCalledTimes(1);
+
+                    // return the event
+                    return $args[0];
                 }
             )->shouldBeCalledTimes(1);
 
@@ -260,7 +271,7 @@ function(CommentEvent $event) use ($comment) {
                 ),
                 Events::PRE_DELETE_EVENT
             )->will(
-                function() use ($comment, $dispatcher) {
+                function($args) use ($comment, $dispatcher) {
                     $dispatcher->dispatch(
                         Argument::that(
                             function(CommentEvent $event) use ($comment) {
@@ -269,6 +280,9 @@ function(CommentEvent $event) use ($comment) {
                         ),
                         Events::POST_DELETE_EVENT
                     )->shouldBeCalledTimes(1);
+
+                    // return the event
+                    return $args[0];
                 }
             )->shouldBeCalledTimes(1);
 
@@ -303,7 +317,7 @@ function(ThreadEvent $event) use ($thread) {
                 ),
                 Events::THREAD_PRE_DELETE_EVENT
             )->will(
-                function() use ($thread, $dispatcher) {
+                function($args) use ($thread, $dispatcher) {
                     $dispatcher->dispatch(
                         Argument::that(
                             function(ThreadEvent $event) use ($thread) {
@@ -312,6 +326,9 @@ function(ThreadEvent $event) use ($thread) {
                         ),
                         Events::THREAD_POST_DELETE_EVENT
                     )->shouldBeCalledTimes(1);
+
+                    // return the event
+                    return $args[0];
                 }
             )->shouldBeCalledTimes(1);
 
@@ -344,7 +361,7 @@ function(ThreadEvent $event) use ($thread) {
                 ),
                 Events::THREAD_PRE_DELETE_EVENT
             )->will(
-                function() use ($thread, $dispatcher) {
+                function($args) use ($thread, $dispatcher) {
                     $dispatcher->dispatch(
                         Argument::that(
                             function(ThreadEvent $event) use ($thread) {
@@ -353,6 +370,9 @@ function(ThreadEvent $event) use ($thread) {
                         ),
                         Events::THREAD_POST_DELETE_EVENT
                     )->shouldBeCalledTimes(1);
+
+                    // return the event
+                    return $args[0];
                 }
             )->shouldBeCalledTimes(1);
 
@@ -379,7 +399,8 @@ function(CommentEvent $event) use ($comment) {
                 }
             ),
             Events::PUBLISH_EVENT
-        )->shouldBeCalledTimes(1);
+        )->shouldBeCalledTimes(1)
+        ->willReturn(new CommentEvent('', '', $this->comment->reveal(), $this->thread->reveal()));
 
         $this->assertEquals($this->comment->reveal(), $this->commentManager->publish($this->comment->reveal()));
         $this->commentEventCollector->dispatch(); // simulate flush of the comments
@@ -398,7 +419,8 @@ function(CommentEvent $event) use ($comment) {
                 }
             ),
             Events::PUBLISH_EVENT
-        )->shouldNotBeCalled();
+        )->shouldNotBeCalled()
+        ->willReturn(new CommentEvent('', '', $this->comment->reveal(), $this->thread->reveal()));
 
         $this->assertEquals($this->comment->reveal(), $this->commentManager->publish($this->comment->reveal()));
         $this->commentEventCollector->dispatch(); // simulate flush of the comments
@@ -418,7 +440,8 @@ function(CommentEvent $event) use ($comment) {
                 }
             ),
             Events::UNPUBLISH_EVENT
-        )->shouldBeCalledTimes(1);
+        )->shouldBeCalledTimes(1)
+        ->willReturn(new CommentEvent('', '', $this->comment->reveal(), $this->thread->reveal()));
 
         $this->assertEquals($this->comment->reveal(), $this->commentManager->unpublish($this->comment->reveal()));
         $this->commentEventCollector->dispatch(); // simulate flush of the comments
@@ -437,7 +460,8 @@ function(CommentEvent $event) use ($comment) {
                 }
             ),
             Events::UNPUBLISH_EVENT
-        )->shouldNotBeCalled();
+        )->shouldNotBeCalled()
+        ->willReturn(new CommentEvent('', '', $this->comment->reveal(), $this->thread->reveal()));
 
         $this->assertEquals($this->comment->reveal(), $this->commentManager->unpublish($this->comment->reveal()));
         $this->commentEventCollector->dispatch(); // simulate flush of the comments
diff --git a/Tests/bootstrap.php b/Tests/bootstrap.php
index 53a1bacd..bdb70242 100644
--- a/Tests/bootstrap.php
+++ b/Tests/bootstrap.php
@@ -14,7 +14,7 @@
 use Symfony\Component\Dotenv\Dotenv;
 
 $file = __DIR__ . '/../vendor/autoload.php';
-if (!file_exists($file)) {
+if (!\file_exists($file)) {
     throw new RuntimeException('Install dependencies to run test suite.');
 }
 
@@ -22,22 +22,22 @@
 
 // Load cached env vars if the .env.local.php file exists
 // Run "composer dump-env prod" to create it (requires symfony/flex >=1.2)
-if (is_array($env = @include dirname(__DIR__) . '/.env.local.php')) {
+if (\is_array($env = @include \dirname(__DIR__) . '/.env.local.php')) {
     $_SERVER += $env;
     $_ENV += $env;
-} elseif (!class_exists(Dotenv::class)) {
+} elseif (!\class_exists(Dotenv::class)) {
     throw new RuntimeException('Please run "composer require symfony/dotenv" to load the ".env" files configuring the application.');
 } else {
-    $path = dirname(__DIR__) . '/Tests/Application/.env';
+    $path = \dirname(__DIR__) . '/Tests/Application/.env';
     $dotenv = new Dotenv();
 
     // load all the .env files
-    if (method_exists($dotenv, 'loadEnv')) {
+    if (\method_exists($dotenv, 'loadEnv')) {
         $dotenv->loadEnv($path);
     } else {
         // fallback code in case your Dotenv component is not 4.2 or higher (when loadEnv() was added)
 
-        if (file_exists($path) || !file_exists($p = "$path.dist")) {
+        if (\file_exists($path) || !\file_exists($p = "$path.dist")) {
             $dotenv->load($path);
         } else {
             $dotenv->load($p);
@@ -47,16 +47,16 @@
             $dotenv->populate(['APP_ENV' => $env = 'dev']);
         }
 
-        if ('test' !== $env && file_exists($p = "$path.local")) {
+        if ('test' !== $env && \file_exists($p = "$path.local")) {
             $dotenv->load($p);
             $env = $_SERVER['APP_ENV'] ?? $_ENV['APP_ENV'] ?? $env;
         }
 
-        if (file_exists($p = "$path.$env")) {
+        if (\file_exists($p = "$path.$env")) {
             $dotenv->load($p);
         }
 
-        if (file_exists($p = "$path.$env.local")) {
+        if (\file_exists($p = "$path.$env.local")) {
             $dotenv->load($p);
         }
     }
@@ -64,4 +64,4 @@
 
 $_SERVER['APP_ENV'] = $_ENV['APP_ENV'] = ($_SERVER['APP_ENV'] ?? $_ENV['APP_ENV'] ?? null) ?: 'dev';
 $_SERVER['APP_DEBUG'] = $_SERVER['APP_DEBUG'] ?? $_ENV['APP_DEBUG'] ?? 'prod' !== $_SERVER['APP_ENV'];
-$_SERVER['APP_DEBUG'] = $_ENV['APP_DEBUG'] = (int) $_SERVER['APP_DEBUG'] || filter_var($_SERVER['APP_DEBUG'], FILTER_VALIDATE_BOOLEAN) ? '1' : '0';
+$_SERVER['APP_DEBUG'] = $_ENV['APP_DEBUG'] = (int) $_SERVER['APP_DEBUG'] || \filter_var($_SERVER['APP_DEBUG'], \FILTER_VALIDATE_BOOLEAN) ? '1' : '0';
diff --git a/Tests/phpstan/console-application.php b/Tests/phpstan/console-application.php
index a01a00e8..c9f390d1 100644
--- a/Tests/phpstan/console-application.php
+++ b/Tests/phpstan/console-application.php
@@ -14,7 +14,7 @@
 use Sulu\Bundle\CommentBundle\Tests\Application\Kernel;
 use Symfony\Bundle\FrameworkBundle\Console\Application;
 
-require dirname(__DIR__) . '/bootstrap.php';
+require \dirname(__DIR__) . '/bootstrap.php';
 
 $kernel = new Kernel($_SERVER['APP_ENV'], (bool) $_SERVER['APP_DEBUG'], Kernel::CONTEXT_ADMIN);
 $kernel->boot();
diff --git a/Tests/phpstan/object-manager.php b/Tests/phpstan/object-manager.php
index 5e94095c..f1c3c1ca 100644
--- a/Tests/phpstan/object-manager.php
+++ b/Tests/phpstan/object-manager.php
@@ -14,7 +14,7 @@
 use Sulu\Bundle\CommentBundle\Tests\Application\Kernel;
 use Symfony\Component\DependencyInjection\ContainerInterface;
 
-require dirname(__DIR__) . '/bootstrap.php';
+require \dirname(__DIR__) . '/bootstrap.php';
 
 $kernel = new Kernel($_SERVER['APP_ENV'], (bool) $_SERVER['APP_DEBUG'], Kernel::CONTEXT_ADMIN);
 $kernel->boot();
diff --git a/composer.json b/composer.json
index 5cba07bc..2667d137 100644
--- a/composer.json
+++ b/composer.json
@@ -4,36 +4,36 @@
     "type": "sulu-bundle",
     "license": "MIT",
     "require": {
-        "php": "^7.2",
+        "php": "^7.2 || ^8.0",
         "friendsofsymfony/rest-bundle": "^2.6 || ^3.0",
-        "sulu/sulu": "^2.0.4",
-        "symfony/config": "^4.3 || ^5.0",
-        "symfony/dependency-injection": "^4.3 || ^5.0",
-        "symfony/framework-bundle": "^4.3 || ^5.0",
-        "symfony/http-foundation": "^4.3 || ^5.0",
-        "symfony/http-kernel": "^4.3 || ^5.0"
+        "sulu/sulu": "^2.0.4 || ^2.5.10@dev",
+        "symfony/config": "^4.3 || ^5.0 || ^6.0",
+        "symfony/dependency-injection": "^4.3 || ^5.0 || ^6.0",
+        "symfony/framework-bundle": "^4.3 || ^5.0 || ^6.0",
+        "symfony/http-foundation": "^4.3 || ^5.0 || ^6.0",
+        "symfony/http-kernel": "^4.3 || ^5.0 || ^6.0"
     },
     "require-dev": {
         "doctrine/doctrine-bundle": "^1.10 || ^2.0",
-        "friendsofphp/php-cs-fixer": "^2.17",
+        "friendsofphp/php-cs-fixer": "^2.17 || ^3.0",
         "handcraftedinthealps/zendsearch": "^2.0",
         "jackalope/jackalope-doctrine-dbal": "^1.3.4",
-        "jangregor/phpstan-prophecy": "^0.5.1",
+        "jangregor/phpstan-prophecy": "^1.0",
         "massive/search-bundle": "^2.0.0",
-        "php-ffmpeg/php-ffmpeg": "^0.13 || ^0.14",
+        "php-ffmpeg/php-ffmpeg": "^0.14 || ^1.0",
         "phpspec/prophecy": "^1.17",
-        "phpstan/phpstan": "^0.12",
-        "phpstan/phpstan-doctrine": "^0.12",
-        "phpstan/phpstan-phpunit": "^0.12",
-        "phpstan/phpstan-symfony": "^0.12",
-        "phpunit/phpunit": "^8.0",
-        "symfony/browser-kit": "^4.3",
-        "symfony/dotenv": "^4.3",
-        "symfony/form": "^4.3",
+        "phpstan/phpstan": "^1.0",
+        "phpstan/phpstan-doctrine": "^1.0",
+        "phpstan/phpstan-phpunit": "^1.0",
+        "phpstan/phpstan-symfony": "^1.0",
+        "phpunit/phpunit": "^8.0 || ^9.0",
+        "symfony/browser-kit": "^4.3 || ^5.0 || ^6.0",
+        "symfony/dotenv": "^4.3 || ^5.0 || ^6.0",
+        "symfony/form": "^4.3 || ^5.0 || ^6.0",
         "symfony/monolog-bundle": "^3.1",
-        "symfony/security-bundle": "^4.3",
-        "symfony/stopwatch": "^4.3",
-        "thecodingmachine/phpstan-strict-rules": "^0.12.2"
+        "symfony/security-bundle": "^4.3 || ^5.0 || ^6.0",
+        "symfony/stopwatch": "^4.3 || ^5.0 || ^6.0",
+        "thecodingmachine/phpstan-strict-rules": "^1.0"
     },
     "keywords": [],
     "authors": [
diff --git a/phpstan-baseline.neon b/phpstan-baseline.neon
deleted file mode 100644
index 82f948bf..00000000
--- a/phpstan-baseline.neon
+++ /dev/null
@@ -1,227 +0,0 @@
-parameters:
-	ignoreErrors:
-		-
-			message: "#^PHPDoc tag @var for variable \\$commentFormToolbarActions has no value type specified in iterable type array\\.$#"
-			count: 1
-			path: Admin/CommentAdmin.php
-
-		-
-			message: "#^Parameter \\#1 \\$message of method Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\CommentInterface\\:\\:setMessage\\(\\) expects string, bool\\|float\\|int\\|string\\|null given\\.$#"
-			count: 1
-			path: Controller/CommentController.php
-
-		-
-			message: "#^Parameter \\#2 \\$value of method Sulu\\\\Component\\\\Rest\\\\ListBuilder\\\\ListBuilderInterface\\:\\:where\\(\\) expects string, array\\<bool\\|float\\|int\\|string\\>\\|bool\\|float\\|int\\|string given\\.$#"
-			count: 1
-			path: Controller/CommentController.php
-
-		-
-			message: "#^Parameter \\#1 \\$title of method Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\ThreadInterface\\:\\:setTitle\\(\\) expects string, bool\\|float\\|int\\|string\\|null given\\.$#"
-			count: 1
-			path: Controller/ThreadController.php
-
-		-
-			message: "#^Parameter \\#2 \\$value of method Sulu\\\\Component\\\\Rest\\\\ListBuilder\\\\ListBuilderInterface\\:\\:where\\(\\) expects string, array\\<bool\\|float\\|int\\|string\\>\\|bool\\|float\\|int\\|string given\\.$#"
-			count: 1
-			path: Controller/ThreadController.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Controller\\\\WebsiteCommentController\\:\\:__construct\\(\\) has parameter \\$commentDefaultTemplates with no value type specified in iterable type array\\.$#"
-			count: 1
-			path: Controller/WebsiteCommentController.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Controller\\\\WebsiteCommentController\\:\\:__construct\\(\\) has parameter \\$commentSerializationGroups with no value type specified in iterable type array\\.$#"
-			count: 1
-			path: Controller/WebsiteCommentController.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Controller\\\\WebsiteCommentController\\:\\:__construct\\(\\) has parameter \\$commentTypes with no value type specified in iterable type array\\.$#"
-			count: 1
-			path: Controller/WebsiteCommentController.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Controller\\\\WebsiteCommentController\\:\\:view\\(\\) has parameter \\$data with no typehint specified\\.$#"
-			count: 1
-			path: Controller/WebsiteCommentController.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Controller\\\\WebsiteCommentController\\:\\:view\\(\\) has parameter \\$headers with no value type specified in iterable type array\\.$#"
-			count: 1
-			path: Controller/WebsiteCommentController.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Controller\\\\WebsiteCommentController\\:\\:view\\(\\) has parameter \\$statusCode with no typehint specified\\.$#"
-			count: 1
-			path: Controller/WebsiteCommentController.php
-
-		-
-			message: "#^Parameter \\#1 \\$message of method Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Comment\\:\\:setMessage\\(\\) expects string, bool\\|float\\|int\\|string\\|null given\\.$#"
-			count: 1
-			path: Controller/WebsiteCommentController.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Controller\\\\WebsiteCommentController\\:\\:\\$commentDefaultTemplates type has no value type specified in iterable type array\\.$#"
-			count: 1
-			path: Controller/WebsiteCommentController.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Controller\\\\WebsiteCommentController\\:\\:\\$commentSerializationGroups type has no value type specified in iterable type array\\.$#"
-			count: 1
-			path: Controller/WebsiteCommentController.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Controller\\\\WebsiteCommentController\\:\\:\\$commentTypes type has no value type specified in iterable type array\\.$#"
-			count: 1
-			path: Controller/WebsiteCommentController.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\DependencyInjection\\\\SuluCommentExtension\\:\\:load\\(\\) has no return typehint specified\\.$#"
-			count: 1
-			path: DependencyInjection/SuluCommentExtension.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\DependencyInjection\\\\SuluCommentExtension\\:\\:prepend\\(\\) has no return typehint specified\\.$#"
-			count: 1
-			path: DependencyInjection/SuluCommentExtension.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Comment\\:\\:getChildren\\(\\) return type with generic interface Doctrine\\\\Common\\\\Collections\\\\Collection does not specify its types\\: TKey, T$#"
-			count: 1
-			path: Entity/Comment.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Comment\\:\\:getPublishedChildren\\(\\) return type with generic interface Doctrine\\\\Common\\\\Collections\\\\Collection does not specify its types\\: TKey, T$#"
-			count: 1
-			path: Entity/Comment.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Comment\\:\\:\\$children type mapping mismatch\\: property can contain Doctrine\\\\Common\\\\Collections\\\\Collection&iterable\\<Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\CommentInterface\\> but database expects Doctrine\\\\Common\\\\Collections\\\\Collection&iterable\\<Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Comment\\>\\.$#"
-			count: 1
-			path: Entity/Comment.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Comment\\:\\:\\$children with generic interface Doctrine\\\\Common\\\\Collections\\\\Collection does not specify its types\\: TKey, T$#"
-			count: 1
-			path: Entity/Comment.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Comment\\:\\:\\$parent type mapping mismatch\\: property can contain Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\CommentInterface\\|null but database expects Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Comment\\|null\\.$#"
-			count: 1
-			path: Entity/Comment.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Comment\\:\\:\\$thread type mapping mismatch\\: property can contain Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\ThreadInterface\\|null but database expects Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Thread\\|null\\.$#"
-			count: 1
-			path: Entity/Comment.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\CommentInterface\\:\\:getChildren\\(\\) return type with generic interface Doctrine\\\\Common\\\\Collections\\\\Collection does not specify its types\\: TKey, T$#"
-			count: 1
-			path: Entity/CommentInterface.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\CommentInterface\\:\\:getPublishedChildren\\(\\) return type with generic interface Doctrine\\\\Common\\\\Collections\\\\Collection does not specify its types\\: TKey, T$#"
-			count: 1
-			path: Entity/CommentInterface.php
-
-		-
-			message: "#^Interface Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\CommentRepositoryInterface extends generic interface Sulu\\\\Component\\\\Persistence\\\\Repository\\\\RepositoryInterface but does not specify its types\\: T$#"
-			count: 1
-			path: Entity/CommentRepositoryInterface.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Thread\\:\\:__construct\\(\\) has parameter \\$comments with generic interface Doctrine\\\\Common\\\\Collections\\\\Collection but does not specify its types\\: TKey, T$#"
-			count: 1
-			path: Entity/Thread.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Thread\\:\\:getComments\\(\\) return type with generic interface Doctrine\\\\Common\\\\Collections\\\\Collection does not specify its types\\: TKey, T$#"
-			count: 1
-			path: Entity/Thread.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Thread\\:\\:\\$changer type mapping mismatch\\: database can contain Sulu\\\\Bundle\\\\SecurityBundle\\\\Entity\\\\User\\|null but property expects Sulu\\\\Component\\\\Security\\\\Authentication\\\\UserInterface\\.$#"
-			count: 1
-			path: Entity/Thread.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Thread\\:\\:\\$changer type mapping mismatch\\: property can contain Sulu\\\\Component\\\\Security\\\\Authentication\\\\UserInterface but database expects Sulu\\\\Bundle\\\\SecurityBundle\\\\Entity\\\\User\\|null\\.$#"
-			count: 1
-			path: Entity/Thread.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Thread\\:\\:\\$comments type mapping mismatch\\: property can contain Doctrine\\\\Common\\\\Collections\\\\Collection but database expects Doctrine\\\\Common\\\\Collections\\\\Collection&iterable\\<Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Comment\\>\\.$#"
-			count: 1
-			path: Entity/Thread.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Thread\\:\\:\\$comments with generic interface Doctrine\\\\Common\\\\Collections\\\\Collection does not specify its types\\: TKey, T$#"
-			count: 1
-			path: Entity/Thread.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Thread\\:\\:\\$creator type mapping mismatch\\: database can contain Sulu\\\\Bundle\\\\SecurityBundle\\\\Entity\\\\User\\|null but property expects Sulu\\\\Component\\\\Security\\\\Authentication\\\\UserInterface\\.$#"
-			count: 1
-			path: Entity/Thread.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Thread\\:\\:\\$creator type mapping mismatch\\: property can contain Sulu\\\\Component\\\\Security\\\\Authentication\\\\UserInterface but database expects Sulu\\\\Bundle\\\\SecurityBundle\\\\Entity\\\\User\\|null\\.$#"
-			count: 1
-			path: Entity/Thread.php
-
-		-
-			message: "#^Property Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\Thread\\:\\:\\$title type mapping mismatch\\: database can contain string\\|null but property expects string\\.$#"
-			count: 1
-			path: Entity/Thread.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\ThreadInterface\\:\\:getComments\\(\\) return type with generic interface Doctrine\\\\Common\\\\Collections\\\\Collection does not specify its types\\: TKey, T$#"
-			count: 1
-			path: Entity/ThreadInterface.php
-
-		-
-			message: "#^Class Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\ThreadRepository extends generic class Doctrine\\\\ORM\\\\EntityRepository but does not specify its types\\: TEntityClass$#"
-			count: 1
-			path: Entity/ThreadRepository.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\ThreadRepository\\:\\:createNew\\(\\) should return Sulu\\\\Bundle\\\\CommentBundle\\\\Entity\\\\ThreadInterface but returns object\\.$#"
-			count: 1
-			path: Entity/ThreadRepository.php
-
-		-
-			message: "#^Call to an undefined method Sulu\\\\Component\\\\Security\\\\Authentication\\\\UserInterface\\:\\:getContact\\(\\)\\.$#"
-			count: 1
-			path: EventSubscriber/CommentSerializationSubscriber.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\EventSubscriber\\\\CommentSerializationSubscriber\\:\\:getSubscribedEvents\\(\\) return type has no value type specified in iterable type array\\.$#"
-			count: 1
-			path: EventSubscriber/CommentSerializationSubscriber.php
-
-		-
-			message: "#^Method Symfony\\\\Contracts\\\\EventDispatcher\\\\EventDispatcherInterface\\:\\:dispatch\\(\\) invoked with 2 parameters, 1 required\\.$#"
-			count: 1
-			path: Events/CommentEventCollector.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Form\\\\Type\\\\CommentType\\:\\:buildForm\\(\\) has no return typehint specified\\.$#"
-			count: 1
-			path: Form/Type/CommentType.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\Form\\\\Type\\\\CommentType\\:\\:configureOptions\\(\\) has no return typehint specified\\.$#"
-			count: 1
-			path: Form/Type/CommentType.php
-
-		-
-			message: "#^Method Symfony\\\\Contracts\\\\EventDispatcher\\\\EventDispatcherInterface\\:\\:dispatch\\(\\) invoked with 2 parameters, 1 required\\.$#"
-			count: 5
-			path: Manager/CommentManager.php
-
-		-
-			message: "#^Method Sulu\\\\Bundle\\\\CommentBundle\\\\SuluCommentBundle\\:\\:build\\(\\) has no return typehint specified\\.$#"
-			count: 1
-			path: SuluCommentBundle.php
-
diff --git a/phpstan.neon b/phpstan.neon
index 645bf047..27fbafdc 100644
--- a/phpstan.neon
+++ b/phpstan.neon
@@ -1,18 +1,17 @@
 includes:
-    - vendor/jangregor/phpstan-prophecy/src/extension.neon
+    - vendor/jangregor/phpstan-prophecy/extension.neon
     - vendor/phpstan/phpstan-doctrine/extension.neon
     - vendor/phpstan/phpstan-doctrine/rules.neon
     - vendor/phpstan/phpstan-symfony/extension.neon
     - vendor/phpstan/phpstan-phpunit/extension.neon
     - vendor/phpstan/phpstan-phpunit/rules.neon
     - vendor/thecodingmachine/phpstan-strict-rules/phpstan-strict-rules.neon
-    - phpstan-baseline.neon
 
 parameters:
     paths:
         - .
     level: max
-    excludes_analyse:
+    excludePaths:
         - %currentWorkingDirectory%/DependencyInjection/Configuration.php
         - %currentWorkingDirectory%/Tests/*
         - %currentWorkingDirectory%/vendor/*
@@ -21,3 +20,6 @@ parameters:
         console_application_loader: Tests/phpstan/console-application.php
     doctrine:
         objectManagerLoader: Tests/phpstan/object-manager.php
+    ignoreErrors:
+        - "#^Property .* type mapping mismatch\\: property can contain .* but database .*$#"
+        - "#^Property .* type mapping mismatch\\: database can contain .* but property .*$#"