diff --git a/composer.json b/composer.json
index 00c64920f60..228872a2b1d 100644
--- a/composer.json
+++ b/composer.json
@@ -21,7 +21,7 @@
         "symfony/http-kernel": "^3.4 || ^4.0",
         "symfony/property-access": "^3.4 || ^4.0",
         "symfony/property-info": "^3.4 || ^4.0",
-        "symfony/serializer": "^4.1",
+        "symfony/serializer": "^4.2",
         "symfony/web-link": "^4.1",
         "willdurand/negotiation": "^2.0.3"
     },
diff --git a/phpstan.neon.dist b/phpstan.neon.dist
index d906bbcda6a..89ab139a10d 100644
--- a/phpstan.neon.dist
+++ b/phpstan.neon.dist
@@ -71,10 +71,6 @@ parameters:
 			message: '#Method ApiPlatform\\Core\\Bridge\\Doctrine\\Orm\\Util\\QueryBuilderHelper::mapJoinAliases() should return array<string, array<string>\|string> but returns array<int|string, mixed>\.#'
 			path: %currentWorkingDirectory%/src/Bridge/Doctrine/Orm/Util/QueryBuilderHelper.php
 		- "#Call to method PHPUnit\\\\Framework\\\\Assert::assertSame\\(\\) with array\\('(collection_context|item_context|subresource_context)'\\) and array<Symfony\\\\Component\\\\VarDumper\\\\Cloner\\\\Data>\\|bool\\|float\\|int\\|string\\|null will always evaluate to false\\.#"
-		# https://github.com/symfony/symfony/pull/30535
-		-
-			message: '#Call to method PHPUnit\\Framework\\Assert::assertNull\(\) with string will always evaluate to false\.#'
-			path: %currentWorkingDirectory%/tests/EventListener/AddFormatListenerTest.php
 		# https://github.com/doctrine/doctrine2/pull/7298/files
 		- '#Strict comparison using === between null and int will always evaluate to false\.#'
 		-