diff --git a/composer.lock b/composer.lock
index f6ee442d6017a6975014322e6afa19fd8de9d1ee..1cd4ce087b603c5d4204a12c6a4672efec411286 100644
--- a/composer.lock
+++ b/composer.lock
@@ -8213,12 +8213,12 @@
             "source": {
                 "type": "git",
                 "url": "https://github.com/TYPO3/testing-framework.git",
-                "reference": "6e8bc19810f1760dd757a9197b0edc0af6ab39f9"
+                "reference": "e6ad4beaca4e982864c7de1da8746aed1e3f932b"
             },
             "dist": {
                 "type": "zip",
-                "url": "https://api.github.com/repos/TYPO3/testing-framework/zipball/6e8bc19810f1760dd757a9197b0edc0af6ab39f9",
-                "reference": "6e8bc19810f1760dd757a9197b0edc0af6ab39f9",
+                "url": "https://api.github.com/repos/TYPO3/testing-framework/zipball/e6ad4beaca4e982864c7de1da8746aed1e3f932b",
+                "reference": "e6ad4beaca4e982864c7de1da8746aed1e3f932b",
                 "shasum": ""
             },
             "require": {
@@ -8274,7 +8274,7 @@
                 "issues": "https://github.com/TYPO3/testing-framework/issues",
                 "source": "https://github.com/TYPO3/testing-framework/tree/main"
             },
-            "time": "2021-11-27T12:47:48+00:00"
+            "time": "2021-11-30T09:50:17+00:00"
         }
     ],
     "aliases": [],
diff --git a/typo3/sysext/adminpanel/Tests/Unit/Middleware/AdminPanelInitiatorTest.php b/typo3/sysext/adminpanel/Tests/Unit/Middleware/AdminPanelInitiatorTest.php
index 137a911ff2fcd868ab03dcaaf0638b4d539f1194..68a73ceb39c38e2d288b400a6d67847d15a9f8a7 100644
--- a/typo3/sysext/adminpanel/Tests/Unit/Middleware/AdminPanelInitiatorTest.php
+++ b/typo3/sysext/adminpanel/Tests/Unit/Middleware/AdminPanelInitiatorTest.php
@@ -39,7 +39,7 @@ class AdminPanelInitiatorTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/backend/Tests/Unit/Controller/EditDocumentControllerTest.php b/typo3/sysext/backend/Tests/Unit/Controller/EditDocumentControllerTest.php
index 7ca75d732917f6ff3af78eddaa004915696cc80c..efd9decf14a1310b713ea19060aa0345d39f6ed5 100644
--- a/typo3/sysext/backend/Tests/Unit/Controller/EditDocumentControllerTest.php
+++ b/typo3/sysext/backend/Tests/Unit/Controller/EditDocumentControllerTest.php
@@ -38,7 +38,7 @@ class EditDocumentControllerTest extends UnitTestCase
     /**
      * @var bool
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/backend/Tests/Unit/Controller/LoginControllerTest.php b/typo3/sysext/backend/Tests/Unit/Controller/LoginControllerTest.php
index 6d2a129d65566a6094fd38308d046b9ddfa0a049..a8db5d7009eed607213c1c0565313a4779994196 100644
--- a/typo3/sysext/backend/Tests/Unit/Controller/LoginControllerTest.php
+++ b/typo3/sysext/backend/Tests/Unit/Controller/LoginControllerTest.php
@@ -39,7 +39,7 @@ class LoginControllerTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var LoginController|MockObject|AccessibleObjectInterface
diff --git a/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/SiteResolvingTest.php b/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/SiteResolvingTest.php
index 08b65e381c48ba8eee133e7cbb2a409080028b09..5b77417b0867e44089d43bdc61f1f43c45bd69b5 100644
--- a/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/SiteResolvingTest.php
+++ b/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/SiteResolvingTest.php
@@ -30,7 +30,7 @@ class SiteResolvingTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaGroupTest.php b/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaGroupTest.php
index 9042a62a98832379fd6c770acc1672f56c5e3b96..ac0a090ca2ae63be6ba6cc876844cb622af4800a 100644
--- a/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaGroupTest.php
+++ b/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaGroupTest.php
@@ -38,7 +38,7 @@ class TcaGroupTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaSelectTreeItemsTest.php b/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaSelectTreeItemsTest.php
index 84835d7779588fea25fa1d2ff8d6f8172c129343..aa963ed044d75f5373a86676cb19959ff614bf93 100644
--- a/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaSelectTreeItemsTest.php
+++ b/typo3/sysext/backend/Tests/Unit/Form/FormDataProvider/TcaSelectTreeItemsTest.php
@@ -51,7 +51,7 @@ class TcaSelectTreeItemsTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Setup a mock database connection with expectations for
diff --git a/typo3/sysext/backend/Tests/Unit/Form/InlineStackProcessorTest.php b/typo3/sysext/backend/Tests/Unit/Form/InlineStackProcessorTest.php
index 7a7a967119e8cc8a4f17d8c370a74d99e7e49a44..e6e2062093fc4f0d135e8f4aa301ecfce50012aa 100644
--- a/typo3/sysext/backend/Tests/Unit/Form/InlineStackProcessorTest.php
+++ b/typo3/sysext/backend/Tests/Unit/Form/InlineStackProcessorTest.php
@@ -34,7 +34,7 @@ class InlineStackProcessorTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     public function setUp(): void
     {
diff --git a/typo3/sysext/backend/Tests/Unit/Utility/BackendUtilityTest.php b/typo3/sysext/backend/Tests/Unit/Utility/BackendUtilityTest.php
index 171b2e1b207ab0d5cb0bba4bce37a9b139aeb9ef..713680ce0b8296cbfef9dc17de9225d132230673 100644
--- a/typo3/sysext/backend/Tests/Unit/Utility/BackendUtilityTest.php
+++ b/typo3/sysext/backend/Tests/Unit/Utility/BackendUtilityTest.php
@@ -44,7 +44,7 @@ class BackendUtilityTest extends UnitTestCase
     /**
      * @var bool
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     ///////////////////////////////////////
     // Tests concerning calcAge
diff --git a/typo3/sysext/backend/Tests/Unit/View/ArrayBrowserTest.php b/typo3/sysext/backend/Tests/Unit/View/ArrayBrowserTest.php
index 4f37cc6564debb253d7ce6f380e72561672e1369..f02fe7d9ba97639e896c11c1be2d1161266d14a7 100644
--- a/typo3/sysext/backend/Tests/Unit/View/ArrayBrowserTest.php
+++ b/typo3/sysext/backend/Tests/Unit/View/ArrayBrowserTest.php
@@ -25,7 +25,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
 
 class ArrayBrowserTest extends UnitTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     ///////////////////////////////
     // Tests concerning depthKeys
diff --git a/typo3/sysext/backend/Tests/Unit/View/BackendLayout/BackendLayoutTest.php b/typo3/sysext/backend/Tests/Unit/View/BackendLayout/BackendLayoutTest.php
index 86d8e6b771a0d44102af989f031c21bcbce37d5b..c27f455d3da26e23d89c1545603842f9008fab1f 100644
--- a/typo3/sysext/backend/Tests/Unit/View/BackendLayout/BackendLayoutTest.php
+++ b/typo3/sysext/backend/Tests/Unit/View/BackendLayout/BackendLayoutTest.php
@@ -32,7 +32,7 @@ class BackendLayoutTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Authentication/AuthenticationServiceTest.php b/typo3/sysext/core/Tests/Unit/Authentication/AuthenticationServiceTest.php
index 25476cdbb38649a004e4a214fb6ef312966d0224..ad71079fbdebd808c861f3c3a8fedd2b91382954 100644
--- a/typo3/sysext/core/Tests/Unit/Authentication/AuthenticationServiceTest.php
+++ b/typo3/sysext/core/Tests/Unit/Authentication/AuthenticationServiceTest.php
@@ -33,7 +33,7 @@ class AuthenticationServiceTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Date provider for processLoginReturnsCorrectData
diff --git a/typo3/sysext/core/Tests/Unit/Authentication/Mfa/Provider/TotpTest.php b/typo3/sysext/core/Tests/Unit/Authentication/Mfa/Provider/TotpTest.php
index c85eb5c44ca10bcdfd9d5246b51a117e90f7f3fd..1cfd72c4de4ef30eebc84793faa4e04067547878 100644
--- a/typo3/sysext/core/Tests/Unit/Authentication/Mfa/Provider/TotpTest.php
+++ b/typo3/sysext/core/Tests/Unit/Authentication/Mfa/Provider/TotpTest.php
@@ -28,7 +28,7 @@ class TotpTest extends UnitTestCase
 {
     protected string $secret;
     protected int $timestamp = 1613652061;
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected function setUp(): void
     {
diff --git a/typo3/sysext/core/Tests/Unit/Cache/Backend/AbstractBackendTest.php b/typo3/sysext/core/Tests/Unit/Cache/Backend/AbstractBackendTest.php
index 523913fd2687470a15bfabd319b36a658f3ce01e..73c12e7f8c4f668b774f9928fae821afdba4f794 100644
--- a/typo3/sysext/core/Tests/Unit/Cache/Backend/AbstractBackendTest.php
+++ b/typo3/sysext/core/Tests/Unit/Cache/Backend/AbstractBackendTest.php
@@ -25,7 +25,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class AbstractBackendTest extends UnitTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Cache/Backend/ApcuBackendTest.php b/typo3/sysext/core/Tests/Unit/Cache/Backend/ApcuBackendTest.php
index aeb8ae2e286e0fa25244d7e3c9763194b8c1c4d2..2b0659757a048b7ea46d83bd6b9680caa1dc5b01 100644
--- a/typo3/sysext/core/Tests/Unit/Cache/Backend/ApcuBackendTest.php
+++ b/typo3/sysext/core/Tests/Unit/Cache/Backend/ApcuBackendTest.php
@@ -32,7 +32,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class ApcuBackendTest extends UnitTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Set up
diff --git a/typo3/sysext/core/Tests/Unit/Cache/Backend/FileBackendTest.php b/typo3/sysext/core/Tests/Unit/Cache/Backend/FileBackendTest.php
index b9291a142cf418c9e43d9bde502a0dbd47ed1b70..7221b8322fa75b15d355d5a9f2ddc4a5e4c152e5 100644
--- a/typo3/sysext/core/Tests/Unit/Cache/Backend/FileBackendTest.php
+++ b/typo3/sysext/core/Tests/Unit/Cache/Backend/FileBackendTest.php
@@ -35,7 +35,7 @@ class FileBackendTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Sets up this testcase
diff --git a/typo3/sysext/core/Tests/Unit/Cache/Backend/TransientMemoryBackendTest.php b/typo3/sysext/core/Tests/Unit/Cache/Backend/TransientMemoryBackendTest.php
index 9d5be0b5f25a216fcf584eef3a38bd3e5996afb7..0f3666e5fe0b3979390997a63ec6f928af4373e9 100644
--- a/typo3/sysext/core/Tests/Unit/Cache/Backend/TransientMemoryBackendTest.php
+++ b/typo3/sysext/core/Tests/Unit/Cache/Backend/TransientMemoryBackendTest.php
@@ -27,7 +27,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class TransientMemoryBackendTest extends UnitTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Cache/Backend/Typo3DatabaseBackendTest.php b/typo3/sysext/core/Tests/Unit/Cache/Backend/Typo3DatabaseBackendTest.php
index 220f3646d50822e895363c584349d469ae00815e..aa690f9b479911c5de856e447d272257ada27282 100644
--- a/typo3/sysext/core/Tests/Unit/Cache/Backend/Typo3DatabaseBackendTest.php
+++ b/typo3/sysext/core/Tests/Unit/Cache/Backend/Typo3DatabaseBackendTest.php
@@ -35,7 +35,7 @@ class Typo3DatabaseBackendTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Configuration/FlexForm/FlexFormToolsTest.php b/typo3/sysext/core/Tests/Unit/Configuration/FlexForm/FlexFormToolsTest.php
index db23a11314e633559650478a9cd73d9535607ea4..60de9e9fa7a6bb1c5224a66b6ed930843c7c140d 100644
--- a/typo3/sysext/core/Tests/Unit/Configuration/FlexForm/FlexFormToolsTest.php
+++ b/typo3/sysext/core/Tests/Unit/Configuration/FlexForm/FlexFormToolsTest.php
@@ -64,7 +64,7 @@ class FlexFormToolsTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Set up
diff --git a/typo3/sysext/core/Tests/Unit/Configuration/SiteConfigurationTest.php b/typo3/sysext/core/Tests/Unit/Configuration/SiteConfigurationTest.php
index c65886291b13931155cf47f06d372dadbd8c153a..a17abb10fbe09fcf3f248182979d51e246c9b790 100644
--- a/typo3/sysext/core/Tests/Unit/Configuration/SiteConfigurationTest.php
+++ b/typo3/sysext/core/Tests/Unit/Configuration/SiteConfigurationTest.php
@@ -32,7 +32,7 @@ class SiteConfigurationTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected ?SiteConfiguration $siteConfiguration;
 
diff --git a/typo3/sysext/core/Tests/Unit/Configuration/TypoScript/ConditionMatching/AbstractConditionMatcherTest.php b/typo3/sysext/core/Tests/Unit/Configuration/TypoScript/ConditionMatching/AbstractConditionMatcherTest.php
index c661ca4099e85c8b42160f5cb3900918d74202ef..1a936cb136ad8e4b9af16d0d83de30db9cf92f06 100644
--- a/typo3/sysext/core/Tests/Unit/Configuration/TypoScript/ConditionMatching/AbstractConditionMatcherTest.php
+++ b/typo3/sysext/core/Tests/Unit/Configuration/TypoScript/ConditionMatching/AbstractConditionMatcherTest.php
@@ -44,7 +44,7 @@ class AbstractConditionMatcherTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * @var AbstractConditionMatcher|\PHPUnit\Framework\MockObject\MockObject|\TYPO3\TestingFramework\Core\AccessibleObjectInterface
diff --git a/typo3/sysext/core/Tests/Unit/DataHandling/DataHandlerTest.php b/typo3/sysext/core/Tests/Unit/DataHandling/DataHandlerTest.php
index 3f7f57c0fe27c51867698362c3c65c8c0b609537..743ed0ddef03818936a777fdb15d07b335ac9013 100644
--- a/typo3/sysext/core/Tests/Unit/DataHandling/DataHandlerTest.php
+++ b/typo3/sysext/core/Tests/Unit/DataHandling/DataHandlerTest.php
@@ -44,7 +44,7 @@ class DataHandlerTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * A backup of registered singleton instances
diff --git a/typo3/sysext/core/Tests/Unit/DataHandling/SlugHelperTest.php b/typo3/sysext/core/Tests/Unit/DataHandling/SlugHelperTest.php
index f25729273d123d84749ac187573636a962eddb70..0bc7b0de50ab27e7e6ac673b9232a873627f6bf2 100644
--- a/typo3/sysext/core/Tests/Unit/DataHandling/SlugHelperTest.php
+++ b/typo3/sysext/core/Tests/Unit/DataHandling/SlugHelperTest.php
@@ -25,7 +25,7 @@ class SlugHelperTest extends UnitTestCase
     /**
      * @var bool
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @return array
diff --git a/typo3/sysext/core/Tests/Unit/DataHandling/SoftReference/AbstractSoftReferenceParserTest.php b/typo3/sysext/core/Tests/Unit/DataHandling/SoftReference/AbstractSoftReferenceParserTest.php
index 119221d3dd26e30e60bdf305b79af9d022455230..28a33d7532354df5d3a61b7cce49f2a93e832924 100644
--- a/typo3/sysext/core/Tests/Unit/DataHandling/SoftReference/AbstractSoftReferenceParserTest.php
+++ b/typo3/sysext/core/Tests/Unit/DataHandling/SoftReference/AbstractSoftReferenceParserTest.php
@@ -39,7 +39,7 @@ abstract class AbstractSoftReferenceParserTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected function getParserByKey($softrefKey): SoftReferenceParserInterface
     {
diff --git a/typo3/sysext/core/Tests/Unit/Database/Query/Restriction/FrontendRestrictionContainerTest.php b/typo3/sysext/core/Tests/Unit/Database/Query/Restriction/FrontendRestrictionContainerTest.php
index 2c04c68b4cde8dba1c90df8364a8d5689a7af194..5d41ebb11f07b1900ff76f6e02f6c871843e26bc 100644
--- a/typo3/sysext/core/Tests/Unit/Database/Query/Restriction/FrontendRestrictionContainerTest.php
+++ b/typo3/sysext/core/Tests/Unit/Database/Query/Restriction/FrontendRestrictionContainerTest.php
@@ -27,7 +27,7 @@ use TYPO3\CMS\Frontend\Authentication\FrontendUserAuthentication;
 
 class FrontendRestrictionContainerTest extends AbstractRestrictionTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     public function frontendStatesDataProvider(): array
     {
diff --git a/typo3/sysext/core/Tests/Unit/Database/Query/Restriction/FrontendWorkspaceRestrictionTest.php b/typo3/sysext/core/Tests/Unit/Database/Query/Restriction/FrontendWorkspaceRestrictionTest.php
index f6bdf06ba6877a17e0931bcc301b90294dc75dab..b5dc6e7d6508bfa4ee6173a8dc4c707ddd8089b7 100644
--- a/typo3/sysext/core/Tests/Unit/Database/Query/Restriction/FrontendWorkspaceRestrictionTest.php
+++ b/typo3/sysext/core/Tests/Unit/Database/Query/Restriction/FrontendWorkspaceRestrictionTest.php
@@ -24,7 +24,7 @@ use TYPO3\CMS\Core\Database\Query\Restriction\FrontendWorkspaceRestriction;
  */
 class FrontendWorkspaceRestrictionTest extends AbstractRestrictionTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Database/Schema/Parser/TableBuilderTest.php b/typo3/sysext/core/Tests/Unit/Database/Schema/Parser/TableBuilderTest.php
index 8b065b0ce54b7697211971df617171a13417faaf..ce57c228802be9b42be2569ba73c19d9eaec7f9d 100644
--- a/typo3/sysext/core/Tests/Unit/Database/Schema/Parser/TableBuilderTest.php
+++ b/typo3/sysext/core/Tests/Unit/Database/Schema/Parser/TableBuilderTest.php
@@ -40,7 +40,7 @@ class TableBuilderTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected ?Table $table;
 
diff --git a/typo3/sysext/core/Tests/Unit/Database/Schema/SqlReaderTest.php b/typo3/sysext/core/Tests/Unit/Database/Schema/SqlReaderTest.php
index 247fad21ff3af82728a6a7482c112e973789e49b..c486a73cb5bc2cf5221ee11342162764adbcd351 100644
--- a/typo3/sysext/core/Tests/Unit/Database/Schema/SqlReaderTest.php
+++ b/typo3/sysext/core/Tests/Unit/Database/Schema/SqlReaderTest.php
@@ -33,7 +33,7 @@ class SqlReaderTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Error/ErrorHandlerTest.php b/typo3/sysext/core/Tests/Unit/Error/ErrorHandlerTest.php
index 0b34fd49f2ed05a676b997dcff75ca5793e55016..e19baa5f47070224ef85dfc735601b2d97933f08 100644
--- a/typo3/sysext/core/Tests/Unit/Error/ErrorHandlerTest.php
+++ b/typo3/sysext/core/Tests/Unit/Error/ErrorHandlerTest.php
@@ -41,7 +41,7 @@ class ErrorHandlerTest extends UnitTestCase
     protected const DEFAULT_ERROR_HANDLER_LEVELS = E_ALL & ~(E_STRICT | E_NOTICE | E_COMPILE_WARNING | E_COMPILE_ERROR | E_CORE_WARNING | E_CORE_ERROR | E_PARSE | E_ERROR);
     protected const DEFAULT_EXCEPTIONAL_ERROR_LEVELS = E_ALL & ~(E_STRICT | E_NOTICE | E_COMPILE_WARNING | E_COMPILE_ERROR | E_CORE_WARNING | E_CORE_ERROR | E_PARSE | E_ERROR | E_DEPRECATED | E_USER_DEPRECATED | E_WARNING | E_USER_ERROR | E_USER_NOTICE | E_USER_WARNING);
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Sets up this test case.
diff --git a/typo3/sysext/core/Tests/Unit/Error/ProductionExceptionHandlerTest.php b/typo3/sysext/core/Tests/Unit/Error/ProductionExceptionHandlerTest.php
index d3efa25199d734b0c1e235f5299959c59853a87a..0debde8369e615c1dfd22ff5f0106292fcc6ca16 100644
--- a/typo3/sysext/core/Tests/Unit/Error/ProductionExceptionHandlerTest.php
+++ b/typo3/sysext/core/Tests/Unit/Error/ProductionExceptionHandlerTest.php
@@ -32,7 +32,7 @@ class ProductionExceptionHandlerTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var \TYPO3\CMS\Core\Error\ProductionExceptionHandler|\PHPUnit\Framework\MockObject\MockObject
diff --git a/typo3/sysext/core/Tests/Unit/Html/RteHtmlParserTest.php b/typo3/sysext/core/Tests/Unit/Html/RteHtmlParserTest.php
index 65cbbb8ad23a1108cccee053dab8a06655a74d47..0501d607a6bf2336175a8ae235bff28cbf21f776 100644
--- a/typo3/sysext/core/Tests/Unit/Html/RteHtmlParserTest.php
+++ b/typo3/sysext/core/Tests/Unit/Html/RteHtmlParserTest.php
@@ -29,7 +29,7 @@ class RteHtmlParserTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected array $procOptions = ['overruleMode' => 'default'];
 
diff --git a/typo3/sysext/core/Tests/Unit/Imaging/GraphicalFunctionsTest.php b/typo3/sysext/core/Tests/Unit/Imaging/GraphicalFunctionsTest.php
index 2aa7d749aa4e279a915fba4d3c5b2d80e3ceb381..a543430aa2c064ef4aae8e2b6b806dd5f9c0755d 100644
--- a/typo3/sysext/core/Tests/Unit/Imaging/GraphicalFunctionsTest.php
+++ b/typo3/sysext/core/Tests/Unit/Imaging/GraphicalFunctionsTest.php
@@ -22,7 +22,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
 
 class GraphicalFunctionsTest extends UnitTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Dataprovider for getScaleForImage
diff --git a/typo3/sysext/core/Tests/Unit/Imaging/IconFactoryTest.php b/typo3/sysext/core/Tests/Unit/Imaging/IconFactoryTest.php
index 4c5cbc97b05629c39a019cf325bddd76b0386751..992403af8ddc91e1950fab71f325a0586965df20 100644
--- a/typo3/sysext/core/Tests/Unit/Imaging/IconFactoryTest.php
+++ b/typo3/sysext/core/Tests/Unit/Imaging/IconFactoryTest.php
@@ -41,7 +41,7 @@ class IconFactoryTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var IconFactory
diff --git a/typo3/sysext/core/Tests/Unit/Imaging/ImageDimensionTest.php b/typo3/sysext/core/Tests/Unit/Imaging/ImageDimensionTest.php
index c0e1f8a3a96999d894b1c1b01e3819c99cdf9d7c..aed9f0267010d0057a97b895584f2accb661c108 100644
--- a/typo3/sysext/core/Tests/Unit/Imaging/ImageDimensionTest.php
+++ b/typo3/sysext/core/Tests/Unit/Imaging/ImageDimensionTest.php
@@ -32,7 +32,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class ImageDimensionTest extends UnitTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     public function givenProcessingInstructionsCalculatesCorrectDimensionDataProvider(): array
     {
diff --git a/typo3/sysext/core/Tests/Unit/Localization/LocalesTest.php b/typo3/sysext/core/Tests/Unit/Localization/LocalesTest.php
index 1ad95356a83ef9160073e3eb72dea692d95782e7..e803bbdd13e518e5f14100f37573afb352a16335 100644
--- a/typo3/sysext/core/Tests/Unit/Localization/LocalesTest.php
+++ b/typo3/sysext/core/Tests/Unit/Localization/LocalesTest.php
@@ -26,7 +26,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class LocalesTest extends UnitTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var string
diff --git a/typo3/sysext/core/Tests/Unit/Localization/TcaSystemLanguageCollectorTest.php b/typo3/sysext/core/Tests/Unit/Localization/TcaSystemLanguageCollectorTest.php
index c6788f493618031d34332a7ecd892d7f98a58079..961c5bd2c69e33f169a4e5188618d2974beab4a5 100644
--- a/typo3/sysext/core/Tests/Unit/Localization/TcaSystemLanguageCollectorTest.php
+++ b/typo3/sysext/core/Tests/Unit/Localization/TcaSystemLanguageCollectorTest.php
@@ -37,7 +37,7 @@ class TcaSystemLanguageCollectorTest extends UnitTestCase
     /**
      * @var bool
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     public function setUp(): void
     {
diff --git a/typo3/sysext/core/Tests/Unit/Mail/FileSpoolTest.php b/typo3/sysext/core/Tests/Unit/Mail/FileSpoolTest.php
index 6f581c63a0f70235e52de2897460c37efed93e93..d370d0668c75707cf4c9253aca32b975b8806688 100644
--- a/typo3/sysext/core/Tests/Unit/Mail/FileSpoolTest.php
+++ b/typo3/sysext/core/Tests/Unit/Mail/FileSpoolTest.php
@@ -33,7 +33,7 @@ class FileSpoolTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected ?FileSpool $subject;
 
diff --git a/typo3/sysext/core/Tests/Unit/Mail/MailMessageTest.php b/typo3/sysext/core/Tests/Unit/Mail/MailMessageTest.php
index 98224b711b0a150a6ceed5b19a6e0492b78deeae..bd1f9075dba375e1b0aae281e2677e1857b73f40 100644
--- a/typo3/sysext/core/Tests/Unit/Mail/MailMessageTest.php
+++ b/typo3/sysext/core/Tests/Unit/Mail/MailMessageTest.php
@@ -30,7 +30,7 @@ class MailMessageTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected ?MailMessage $subject;
 
diff --git a/typo3/sysext/core/Tests/Unit/Mail/MailerTest.php b/typo3/sysext/core/Tests/Unit/Mail/MailerTest.php
index 3aed5869e2f908aa2ebf062a5b3bdd9bf0d3861c..0445a55014ad092c1a5031a639c18cc83c8a1958 100644
--- a/typo3/sysext/core/Tests/Unit/Mail/MailerTest.php
+++ b/typo3/sysext/core/Tests/Unit/Mail/MailerTest.php
@@ -44,7 +44,7 @@ class MailerTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var Mailer
diff --git a/typo3/sysext/core/Tests/Unit/Mail/TransportFactoryTest.php b/typo3/sysext/core/Tests/Unit/Mail/TransportFactoryTest.php
index 5752fbcddeb9969e6436c004da2f84fe58422985..ccb3ab8f469ba03213953ca62b2a57149cbdc6b0 100644
--- a/typo3/sysext/core/Tests/Unit/Mail/TransportFactoryTest.php
+++ b/typo3/sysext/core/Tests/Unit/Mail/TransportFactoryTest.php
@@ -48,7 +48,7 @@ class TransportFactoryTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected function getSubject(&$eventDispatcher): TransportFactory
     {
diff --git a/typo3/sysext/core/Tests/Unit/MetaTag/MetaTagManagerRegistryTest.php b/typo3/sysext/core/Tests/Unit/MetaTag/MetaTagManagerRegistryTest.php
index ea3ab6c5e21eb90538b5f52eaeaf5aa1f061beb5..e3637398b6b8bc935f8b0c0fd0db4b6fb988d1d0 100644
--- a/typo3/sysext/core/Tests/Unit/MetaTag/MetaTagManagerRegistryTest.php
+++ b/typo3/sysext/core/Tests/Unit/MetaTag/MetaTagManagerRegistryTest.php
@@ -32,7 +32,7 @@ class MetaTagManagerRegistryTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Resource/Driver/LocalDriverTest.php b/typo3/sysext/core/Tests/Unit/Resource/Driver/LocalDriverTest.php
index 2eb25ce176ce3cd6e524e0cf5ad31bc8b4126263..3938512e77ae8a77ff40369392210d1740ed08bc 100644
--- a/typo3/sysext/core/Tests/Unit/Resource/Driver/LocalDriverTest.php
+++ b/typo3/sysext/core/Tests/Unit/Resource/Driver/LocalDriverTest.php
@@ -38,12 +38,12 @@ class LocalDriverTest extends BaseTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var bool Reset changed Environment
      */
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     protected ?LocalDriver $localDriver;
     protected array $testDirs = [];
diff --git a/typo3/sysext/core/Tests/Unit/Resource/FileTest.php b/typo3/sysext/core/Tests/Unit/Resource/FileTest.php
index fe8e725e7f6ae40cc54f307262cc71397a11a486..d6087a42cc6c1ddbdb609b9c534b2b2452889e4a 100644
--- a/typo3/sysext/core/Tests/Unit/Resource/FileTest.php
+++ b/typo3/sysext/core/Tests/Unit/Resource/FileTest.php
@@ -35,7 +35,7 @@ class FileTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var ResourceStorage
diff --git a/typo3/sysext/core/Tests/Unit/Resource/FolderTest.php b/typo3/sysext/core/Tests/Unit/Resource/FolderTest.php
index eb5cd55efa19786b59363435c626ac2fbe5b376a..c382b93c84cc9c93e7e9c025dd225c5658c6d399 100644
--- a/typo3/sysext/core/Tests/Unit/Resource/FolderTest.php
+++ b/typo3/sysext/core/Tests/Unit/Resource/FolderTest.php
@@ -33,7 +33,7 @@ class FolderTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected string $basedir = 'basedir';
 
diff --git a/typo3/sysext/core/Tests/Unit/Resource/ProcessedFileTest.php b/typo3/sysext/core/Tests/Unit/Resource/ProcessedFileTest.php
index 09ed6b1c03beaf23eb37a35110d44d4e55d7cca3..6212c3d59ee8d1d1e6ec83af8c600c9dd6e9e978 100644
--- a/typo3/sysext/core/Tests/Unit/Resource/ProcessedFileTest.php
+++ b/typo3/sysext/core/Tests/Unit/Resource/ProcessedFileTest.php
@@ -34,7 +34,7 @@ class ProcessedFileTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var MockObject|Folder
diff --git a/typo3/sysext/core/Tests/Unit/Resource/Processing/ProcessorRegistryTest.php b/typo3/sysext/core/Tests/Unit/Resource/Processing/ProcessorRegistryTest.php
index 6beb2becabafb55663d4de7e6c7a120f2d2b502b..c26c566f599fc934a8a5c6a59ff282927ca0e6e7 100644
--- a/typo3/sysext/core/Tests/Unit/Resource/Processing/ProcessorRegistryTest.php
+++ b/typo3/sysext/core/Tests/Unit/Resource/Processing/ProcessorRegistryTest.php
@@ -30,7 +30,7 @@ class ProcessorRegistryTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Resource/RelativeCssPathFixerTest.php b/typo3/sysext/core/Tests/Unit/Resource/RelativeCssPathFixerTest.php
index a1a3d3ae60236b5ddbb8a013adb4dd5e5625813f..d553a925ce1fd301fe1c47010a89012cbee952d6 100644
--- a/typo3/sysext/core/Tests/Unit/Resource/RelativeCssPathFixerTest.php
+++ b/typo3/sysext/core/Tests/Unit/Resource/RelativeCssPathFixerTest.php
@@ -27,7 +27,7 @@ class RelativeCssPathFixerTest extends BaseTestCase
     /**
      * @var bool Restore Environment after tests
      */
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * @return array
diff --git a/typo3/sysext/core/Tests/Unit/Resource/ResourceCompressorIntegrationTest.php b/typo3/sysext/core/Tests/Unit/Resource/ResourceCompressorIntegrationTest.php
index 5dd80407cc4e960cc8068a571e3406beb8ec6f04..012c2bb9f092bf681d72e9270ebab32ce6e781ef 100644
--- a/typo3/sysext/core/Tests/Unit/Resource/ResourceCompressorIntegrationTest.php
+++ b/typo3/sysext/core/Tests/Unit/Resource/ResourceCompressorIntegrationTest.php
@@ -29,7 +29,7 @@ class ResourceCompressorIntegrationTest extends BaseTestCase
     /**
      * @var bool Restore Environment after tests
      */
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     protected ?TestableResourceCompressor $resourceCompressor;
     protected ?string $fixtureDir;
diff --git a/typo3/sysext/core/Tests/Unit/Resource/ResourceCompressorTest.php b/typo3/sysext/core/Tests/Unit/Resource/ResourceCompressorTest.php
index 3b2300f7cd80ec9a918c36e252119052a0c12947..5fa452efe65efe91a366ce9558a066cc03850dcb 100644
--- a/typo3/sysext/core/Tests/Unit/Resource/ResourceCompressorTest.php
+++ b/typo3/sysext/core/Tests/Unit/Resource/ResourceCompressorTest.php
@@ -31,7 +31,7 @@ class ResourceCompressorTest extends BaseTestCase
     /**
      * @var bool Restore Environment after tests
      */
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * @var ResourceCompressor|MockObject|AccessibleObjectInterface
diff --git a/typo3/sysext/core/Tests/Unit/Resource/ResourceFactoryTest.php b/typo3/sysext/core/Tests/Unit/Resource/ResourceFactoryTest.php
index 340d11da5d747a35f99c4b70e53e5d8783dfa72e..3bf4abb942657201bdfd36f2d2e88eabce644861 100644
--- a/typo3/sysext/core/Tests/Unit/Resource/ResourceFactoryTest.php
+++ b/typo3/sysext/core/Tests/Unit/Resource/ResourceFactoryTest.php
@@ -33,9 +33,9 @@ class ResourceFactoryTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * @var ResourceFactory
diff --git a/typo3/sysext/core/Tests/Unit/Resource/ResourceStorageTest.php b/typo3/sysext/core/Tests/Unit/Resource/ResourceStorageTest.php
index af71c73f789bd65c6744d153cf245d65fd1735fb..5eced5e71b6045f37d7eb6e09f4fc49f510dd0d4 100644
--- a/typo3/sysext/core/Tests/Unit/Resource/ResourceStorageTest.php
+++ b/typo3/sysext/core/Tests/Unit/Resource/ResourceStorageTest.php
@@ -49,7 +49,7 @@ class ResourceStorageTest extends BaseTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var ResourceStorage|MockObject
diff --git a/typo3/sysext/core/Tests/Unit/Routing/PageRouterTest.php b/typo3/sysext/core/Tests/Unit/Routing/PageRouterTest.php
index 62452e265fa676654823404a4b1f6c0902e0621a..bbd2782b7e4952349291ee15fa56d02b9c64c649 100644
--- a/typo3/sysext/core/Tests/Unit/Routing/PageRouterTest.php
+++ b/typo3/sysext/core/Tests/Unit/Routing/PageRouterTest.php
@@ -36,7 +36,7 @@ class PageRouterTest extends UnitTestCase
     /**
      * @var bool
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Service/FlexFormServiceTest.php b/typo3/sysext/core/Tests/Unit/Service/FlexFormServiceTest.php
index 48f9883ccbf23346ee5f09e43164beac07559f5d..c39f7b9c2b7d0466677f9a9283d2e7f79e6123c3 100644
--- a/typo3/sysext/core/Tests/Unit/Service/FlexFormServiceTest.php
+++ b/typo3/sysext/core/Tests/Unit/Service/FlexFormServiceTest.php
@@ -31,7 +31,7 @@ class FlexFormServiceTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Service/MarkerBasedTemplateServiceTest.php b/typo3/sysext/core/Tests/Unit/Service/MarkerBasedTemplateServiceTest.php
index 84ca31661f87346650fd8591cde9c2909c83fbfc..28368ba44acf738c03e7ef4b338c4105da052053 100644
--- a/typo3/sysext/core/Tests/Unit/Service/MarkerBasedTemplateServiceTest.php
+++ b/typo3/sysext/core/Tests/Unit/Service/MarkerBasedTemplateServiceTest.php
@@ -38,7 +38,7 @@ class MarkerBasedTemplateServiceTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Set up
diff --git a/typo3/sysext/core/Tests/Unit/TypoScript/Parser/ConstantConfigurationParserTest.php b/typo3/sysext/core/Tests/Unit/TypoScript/Parser/ConstantConfigurationParserTest.php
index d36244bd139c864f28d5dcd605d81e3a687719aa..849867a7bbae1d95184335ca381404d2c25ebbdf 100644
--- a/typo3/sysext/core/Tests/Unit/TypoScript/Parser/ConstantConfigurationParserTest.php
+++ b/typo3/sysext/core/Tests/Unit/TypoScript/Parser/ConstantConfigurationParserTest.php
@@ -24,7 +24,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
 
 class ConstantConfigurationParserTest extends UnitTestCase
 {
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Utility/ExtensionManagementUtilityTest.php b/typo3/sysext/core/Tests/Unit/Utility/ExtensionManagementUtilityTest.php
index 9652de2877055c60e5e5f218361d7cde43cc371f..24afc4b3c4d4b3bce443f217328bf10175117652 100644
--- a/typo3/sysext/core/Tests/Unit/Utility/ExtensionManagementUtilityTest.php
+++ b/typo3/sysext/core/Tests/Unit/Utility/ExtensionManagementUtilityTest.php
@@ -44,7 +44,7 @@ class ExtensionManagementUtilityTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected ?PackageManager $backUpPackageManager;
 
diff --git a/typo3/sysext/core/Tests/Unit/Utility/GeneralUtilityTest.php b/typo3/sysext/core/Tests/Unit/Utility/GeneralUtilityTest.php
index 8cf303e84cc3bdf03c16b1ba019886d19d930ccf..e8aaf16c1403122cb7b664f8943e39c7eae68af6 100644
--- a/typo3/sysext/core/Tests/Unit/Utility/GeneralUtilityTest.php
+++ b/typo3/sysext/core/Tests/Unit/Utility/GeneralUtilityTest.php
@@ -56,12 +56,12 @@ class GeneralUtilityTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var bool Restore Environment after tests
      */
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     protected ?PackageManager $backupPackageManager;
 
diff --git a/typo3/sysext/core/Tests/Unit/Utility/MailUtilityTest.php b/typo3/sysext/core/Tests/Unit/Utility/MailUtilityTest.php
index b12ebac531b2a2bfc503d2158af718a55247dd2a..ed7b1cd4a6456d7a69e1f12f69ce9624101969f1 100644
--- a/typo3/sysext/core/Tests/Unit/Utility/MailUtilityTest.php
+++ b/typo3/sysext/core/Tests/Unit/Utility/MailUtilityTest.php
@@ -28,7 +28,7 @@ class MailUtilityTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/Unit/Utility/PathUtilityPublicPathsTest.php b/typo3/sysext/core/Tests/Unit/Utility/PathUtilityPublicPathsTest.php
index c7a8a699b4ec538b7ac42f65ba0ad78d2ed21eb3..06cb6694e0464bc9882e6c13fdc46b3d6da5367f 100644
--- a/typo3/sysext/core/Tests/Unit/Utility/PathUtilityPublicPathsTest.php
+++ b/typo3/sysext/core/Tests/Unit/Utility/PathUtilityPublicPathsTest.php
@@ -27,7 +27,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class PathUtilityPublicPathsTest extends UnitTestCase
 {
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     protected array $serverBackup;
 
diff --git a/typo3/sysext/core/Tests/Unit/Utility/PathUtilityTest.php b/typo3/sysext/core/Tests/Unit/Utility/PathUtilityTest.php
index 3a3e98831e452f3e85c791cee5bdf9b5b3ee848f..4e6bfc88f3d5610c8cc841835b1b32a4a0806d64 100644
--- a/typo3/sysext/core/Tests/Unit/Utility/PathUtilityTest.php
+++ b/typo3/sysext/core/Tests/Unit/Utility/PathUtilityTest.php
@@ -31,7 +31,7 @@ class PathUtilityTest extends UnitTestCase
      * Restore Environment after the test
      * @var bool
      */
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * @param array $paths
diff --git a/typo3/sysext/core/Tests/UnitDeprecated/Utility/ExtensionManagementUtilityTest.php b/typo3/sysext/core/Tests/UnitDeprecated/Utility/ExtensionManagementUtilityTest.php
index b31f07d50e1530cd80345876aaee2b6932dd1878..00cc61af3abcbaff5322d72f3bd4d72397324767 100644
--- a/typo3/sysext/core/Tests/UnitDeprecated/Utility/ExtensionManagementUtilityTest.php
+++ b/typo3/sysext/core/Tests/UnitDeprecated/Utility/ExtensionManagementUtilityTest.php
@@ -28,7 +28,7 @@ class ExtensionManagementUtilityTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/core/Tests/UnitDeprecated/Utility/PathUtilityPublicPathsTest.php b/typo3/sysext/core/Tests/UnitDeprecated/Utility/PathUtilityPublicPathsTest.php
index 56eac433c58cb5ed2b62ccf2c8d6e95cf2beff35..55456eb2f7aa7ca575f0bafb941c814a64be2127 100644
--- a/typo3/sysext/core/Tests/UnitDeprecated/Utility/PathUtilityPublicPathsTest.php
+++ b/typo3/sysext/core/Tests/UnitDeprecated/Utility/PathUtilityPublicPathsTest.php
@@ -27,7 +27,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class PathUtilityPublicPathsTest extends UnitTestCase
 {
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     protected array $serverBackup;
 
diff --git a/typo3/sysext/dashboard/Tests/Unit/DashboardPresetRegistryTest.php b/typo3/sysext/dashboard/Tests/Unit/DashboardPresetRegistryTest.php
index ed98a1597e99a2a5b525f4d58ae0d1468a5a1c5f..b736e019fe8d71f7e626f6856a18786967b36363 100644
--- a/typo3/sysext/dashboard/Tests/Unit/DashboardPresetRegistryTest.php
+++ b/typo3/sysext/dashboard/Tests/Unit/DashboardPresetRegistryTest.php
@@ -27,7 +27,7 @@ class DashboardPresetRegistryTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /** @var DashboardPresetRegistry  */
     protected $subject;
diff --git a/typo3/sysext/dashboard/Tests/Unit/WidgetGroupRegistryTest.php b/typo3/sysext/dashboard/Tests/Unit/WidgetGroupRegistryTest.php
index 7a8a00c8dd3f566f8a8f8f1cdfddba08299858a9..b68dfdf972d5c3169b867ac0224c3edbd0c04fe5 100644
--- a/typo3/sysext/dashboard/Tests/Unit/WidgetGroupRegistryTest.php
+++ b/typo3/sysext/dashboard/Tests/Unit/WidgetGroupRegistryTest.php
@@ -27,7 +27,7 @@ class WidgetGroupRegistryTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /** @var WidgetGroupRegistry  */
     protected $subject;
diff --git a/typo3/sysext/dashboard/Tests/Unit/WidgetRegistryTest.php b/typo3/sysext/dashboard/Tests/Unit/WidgetRegistryTest.php
index 4147e4acbefa9795be3c3ba863789c41ada59ea3..d3af86030781fe70c6999e9c5e8327135ec2a4f0 100644
--- a/typo3/sysext/dashboard/Tests/Unit/WidgetRegistryTest.php
+++ b/typo3/sysext/dashboard/Tests/Unit/WidgetRegistryTest.php
@@ -33,7 +33,7 @@ class WidgetRegistryTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected WidgetRegistry $subject;
 
diff --git a/typo3/sysext/extbase/Tests/Unit/Configuration/AbstractConfigurationManagerTest.php b/typo3/sysext/extbase/Tests/Unit/Configuration/AbstractConfigurationManagerTest.php
index e93dbe740d74eab14ab7ace1e7cc640b1daa9eac..1344f94a86b4d8d901f49b1e1c6ee920b85850ee 100644
--- a/typo3/sysext/extbase/Tests/Unit/Configuration/AbstractConfigurationManagerTest.php
+++ b/typo3/sysext/extbase/Tests/Unit/Configuration/AbstractConfigurationManagerTest.php
@@ -29,7 +29,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class AbstractConfigurationManagerTest extends UnitTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var AbstractConfigurationManager|MockObject|AccessibleObjectInterface
diff --git a/typo3/sysext/extbase/Tests/Unit/Mvc/Controller/ActionControllerTest.php b/typo3/sysext/extbase/Tests/Unit/Mvc/Controller/ActionControllerTest.php
index 926ba01b487df7c2554115e38b29f9ea2d685528..d710e2a0b7bd712a427863a6c2fcb16fd7194b30 100644
--- a/typo3/sysext/extbase/Tests/Unit/Mvc/Controller/ActionControllerTest.php
+++ b/typo3/sysext/extbase/Tests/Unit/Mvc/Controller/ActionControllerTest.php
@@ -56,7 +56,7 @@ class ActionControllerTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var ActionController|MockObject|AccessibleObjectInterface
diff --git a/typo3/sysext/extbase/Tests/Unit/Mvc/View/JsonViewTest.php b/typo3/sysext/extbase/Tests/Unit/Mvc/View/JsonViewTest.php
index b580ce95c8a0c52705ea951147c8f9d12ae3a6ec..26f0610b1ce92cdab8fe905e0c471a69fa6b1b8d 100644
--- a/typo3/sysext/extbase/Tests/Unit/Mvc/View/JsonViewTest.php
+++ b/typo3/sysext/extbase/Tests/Unit/Mvc/View/JsonViewTest.php
@@ -30,7 +30,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class JsonViewTest extends UnitTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var JsonView
diff --git a/typo3/sysext/extbase/Tests/Unit/Mvc/Web/Routing/UriBuilderTest.php b/typo3/sysext/extbase/Tests/Unit/Mvc/Web/Routing/UriBuilderTest.php
index 4bfbd824b2d1cea861b56a1bafc3a7d422f7944b..d3f9ebb5c99c33c2a091fb857e8f54fdd8709341 100644
--- a/typo3/sysext/extbase/Tests/Unit/Mvc/Web/Routing/UriBuilderTest.php
+++ b/typo3/sysext/extbase/Tests/Unit/Mvc/Web/Routing/UriBuilderTest.php
@@ -49,7 +49,7 @@ class UriBuilderTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var ConfigurationManagerInterface
diff --git a/typo3/sysext/extbase/Tests/Unit/Object/Container/ContainerTest.php b/typo3/sysext/extbase/Tests/Unit/Object/Container/ContainerTest.php
index a409cc0fb45a0e93e3811a975bcd11faed6eab92..36f7792aa5263dea6ec32e6ebacd80a875205359 100644
--- a/typo3/sysext/extbase/Tests/Unit/Object/Container/ContainerTest.php
+++ b/typo3/sysext/extbase/Tests/Unit/Object/Container/ContainerTest.php
@@ -46,7 +46,7 @@ class ContainerTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var Container
diff --git a/typo3/sysext/extbase/Tests/Unit/Persistence/Generic/Storage/Typo3DbBackendTest.php b/typo3/sysext/extbase/Tests/Unit/Persistence/Generic/Storage/Typo3DbBackendTest.php
index 1d915634ba0221dafc598982ce87bd8edc8d8abc..3d889243ecf68665cc8425c05e8ab0e886c56fa9 100644
--- a/typo3/sysext/extbase/Tests/Unit/Persistence/Generic/Storage/Typo3DbBackendTest.php
+++ b/typo3/sysext/extbase/Tests/Unit/Persistence/Generic/Storage/Typo3DbBackendTest.php
@@ -54,7 +54,7 @@ class Typo3DbBackendTest extends UnitTestCase
      * Due to nested PageRepository / FrontendRestriction Container issues, the Context object is set
      * @var bool
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @return array
diff --git a/typo3/sysext/extbase/Tests/Unit/Reflection/ObjectAccessTest.php b/typo3/sysext/extbase/Tests/Unit/Reflection/ObjectAccessTest.php
index c5f83b486ad8f6d8f65ca2d25d353ef9e10776b4..c99f8ab93c948330509f5076d15b377b4381d622 100644
--- a/typo3/sysext/extbase/Tests/Unit/Reflection/ObjectAccessTest.php
+++ b/typo3/sysext/extbase/Tests/Unit/Reflection/ObjectAccessTest.php
@@ -35,7 +35,7 @@ class ObjectAccessTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected DummyClassWithGettersAndSetters $dummyObject;
 
diff --git a/typo3/sysext/extbase/Tests/Unit/Service/ExtensionServiceTest.php b/typo3/sysext/extbase/Tests/Unit/Service/ExtensionServiceTest.php
index 87cb52ecd7b89a213b968fb5dcc8fc676de52cb0..9657ffc0c93d2d859e6804edec61472410ef063d 100644
--- a/typo3/sysext/extbase/Tests/Unit/Service/ExtensionServiceTest.php
+++ b/typo3/sysext/extbase/Tests/Unit/Service/ExtensionServiceTest.php
@@ -50,7 +50,7 @@ class ExtensionServiceTest extends UnitTestCase
      * Due to nested PageRepository / FrontendRestriction Container issues, the Context object is set
      * @var bool
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected function setUp(): void
     {
diff --git a/typo3/sysext/extbase/Tests/Unit/Service/ImageScriptServiceTest.php b/typo3/sysext/extbase/Tests/Unit/Service/ImageScriptServiceTest.php
index 580eb125e7519d9c1814fe5ef5a21eeac9d5e7ca..38a4f39bd55b7435a7d894d713c0c577914f61e0 100644
--- a/typo3/sysext/extbase/Tests/Unit/Service/ImageScriptServiceTest.php
+++ b/typo3/sysext/extbase/Tests/Unit/Service/ImageScriptServiceTest.php
@@ -34,7 +34,7 @@ class ImageScriptServiceTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected ImageService $subject;
 
diff --git a/typo3/sysext/extbase/Tests/UnitDeprecated/Object/Container/ContainerTest.php b/typo3/sysext/extbase/Tests/UnitDeprecated/Object/Container/ContainerTest.php
index d782d7490dbe5987acffb36a71a5e4ae77aa4f8a..55e8cabe22e62e0c89132b27440345244229af85 100644
--- a/typo3/sysext/extbase/Tests/UnitDeprecated/Object/Container/ContainerTest.php
+++ b/typo3/sysext/extbase/Tests/UnitDeprecated/Object/Container/ContainerTest.php
@@ -36,7 +36,7 @@ class ContainerTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var Container
diff --git a/typo3/sysext/extbase/Tests/UnitDeprecated/SignalSlot/DispatcherTest.php b/typo3/sysext/extbase/Tests/UnitDeprecated/SignalSlot/DispatcherTest.php
index 161ef8ab8b6dc2d5e4458868a812566afd26a878..df118ae0c124265908b9b83e11502019aa4c01c4 100644
--- a/typo3/sysext/extbase/Tests/UnitDeprecated/SignalSlot/DispatcherTest.php
+++ b/typo3/sysext/extbase/Tests/UnitDeprecated/SignalSlot/DispatcherTest.php
@@ -39,7 +39,7 @@ class DispatcherTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var ObjectManagerInterface|ObjectProphecy
diff --git a/typo3/sysext/extensionmanager/Tests/Unit/Utility/InstallUtilityTest.php b/typo3/sysext/extensionmanager/Tests/Unit/Utility/InstallUtilityTest.php
index 064891baf71384abd2fdafb1a2d0a295a1dd9a0f..c23143b6bd26ac5054cadc55e9eb0303655b6b79 100644
--- a/typo3/sysext/extensionmanager/Tests/Unit/Utility/InstallUtilityTest.php
+++ b/typo3/sysext/extensionmanager/Tests/Unit/Utility/InstallUtilityTest.php
@@ -57,9 +57,9 @@ class InstallUtilityTest extends UnitTestCase
      */
     protected $fakedExtensions = [];
 
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var \PHPUnit\Framework\MockObject\MockObject|InstallUtility|\TYPO3\TestingFramework\Core\AccessibleObjectInterface
diff --git a/typo3/sysext/felogin/Tests/Unit/Redirect/RedirectHandlerTest.php b/typo3/sysext/felogin/Tests/Unit/Redirect/RedirectHandlerTest.php
index bebad9657245ee1960925664c0ec3590fb07ae03..7b628cb496e507ea154c850df98c7e26d631ecb7 100644
--- a/typo3/sysext/felogin/Tests/Unit/Redirect/RedirectHandlerTest.php
+++ b/typo3/sysext/felogin/Tests/Unit/Redirect/RedirectHandlerTest.php
@@ -38,7 +38,7 @@ class RedirectHandlerTest extends UnitTestCase
      *
      * @var bool
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var RedirectHandler
diff --git a/typo3/sysext/felogin/Tests/Unit/Service/RecoveryServiceTest.php b/typo3/sysext/felogin/Tests/Unit/Service/RecoveryServiceTest.php
index 63fa0b6c06f84c4bdd538b76fc13f99f78cb1f7b..4df4e7746228b11f8a99fefa19ba75900b4881ac 100644
--- a/typo3/sysext/felogin/Tests/Unit/Service/RecoveryServiceTest.php
+++ b/typo3/sysext/felogin/Tests/Unit/Service/RecoveryServiceTest.php
@@ -40,7 +40,7 @@ class RecoveryServiceTest extends UnitTestCase
     /**
      * @var bool
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var FrontendUserRepository|ObjectProphecy
diff --git a/typo3/sysext/felogin/Tests/Unit/Validation/RedirectUrlValidatorTest.php b/typo3/sysext/felogin/Tests/Unit/Validation/RedirectUrlValidatorTest.php
index 71eb06d49d4deb7d9006bb1752136eb902944125..c5491bd21e40df6cabc753d6c13554df96043c8d 100644
--- a/typo3/sysext/felogin/Tests/Unit/Validation/RedirectUrlValidatorTest.php
+++ b/typo3/sysext/felogin/Tests/Unit/Validation/RedirectUrlValidatorTest.php
@@ -35,7 +35,7 @@ class RedirectUrlValidatorTest extends UnitTestCase
     /**
      * @var bool Restore Environment after tests
      */
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * @var RedirectUrlValidator|\TYPO3\TestingFramework\Core\AccessibleObjectInterface
@@ -52,7 +52,7 @@ class RedirectUrlValidatorTest extends UnitTestCase
      */
     protected $testSitePath;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Set up
diff --git a/typo3/sysext/form/Tests/Unit/Controller/FormEditorControllerTest.php b/typo3/sysext/form/Tests/Unit/Controller/FormEditorControllerTest.php
index 727f6364ee182c62b1229eb79865a5f612078498..989607926053effc2d5b26135d1116c533e0de57 100644
--- a/typo3/sysext/form/Tests/Unit/Controller/FormEditorControllerTest.php
+++ b/typo3/sysext/form/Tests/Unit/Controller/FormEditorControllerTest.php
@@ -31,7 +31,7 @@ class FormEditorControllerTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Set up
diff --git a/typo3/sysext/form/Tests/Unit/Controller/FormManagerControllerTest.php b/typo3/sysext/form/Tests/Unit/Controller/FormManagerControllerTest.php
index 24fc038d8b4fac27ecbf9043c5850ff9e01ad5ea..3a6d442fa8f8ebe65d69ec22817d180e92da7a00 100644
--- a/typo3/sysext/form/Tests/Unit/Controller/FormManagerControllerTest.php
+++ b/typo3/sysext/form/Tests/Unit/Controller/FormManagerControllerTest.php
@@ -39,7 +39,7 @@ class FormManagerControllerTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/form/Tests/Unit/Domain/Configuration/FormDefinitionConversionServiceTest.php b/typo3/sysext/form/Tests/Unit/Domain/Configuration/FormDefinitionConversionServiceTest.php
index 02f15d1f5e145d34754056de912b5affa5dfb84d..903dc01a5160bbf5b61edbf2af3f6aaf3b8a8c42 100644
--- a/typo3/sysext/form/Tests/Unit/Domain/Configuration/FormDefinitionConversionServiceTest.php
+++ b/typo3/sysext/form/Tests/Unit/Domain/Configuration/FormDefinitionConversionServiceTest.php
@@ -27,7 +27,7 @@ class FormDefinitionConversionServiceTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/form/Tests/Unit/Domain/Finishers/RedirectFinisherTest.php b/typo3/sysext/form/Tests/Unit/Domain/Finishers/RedirectFinisherTest.php
index a090069fe2288189e6da8a2c0fab77e8eaa57505..52c9e625e1de7a84733f88efadb59cb8dbcb18ed 100644
--- a/typo3/sysext/form/Tests/Unit/Domain/Finishers/RedirectFinisherTest.php
+++ b/typo3/sysext/form/Tests/Unit/Domain/Finishers/RedirectFinisherTest.php
@@ -37,7 +37,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
 class RedirectFinisherTest extends UnitTestCase
 {
     use \Prophecy\PhpUnit\ProphecyTrait;
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/form/Tests/Unit/Domain/FormElements/AbstractSectionTest.php b/typo3/sysext/form/Tests/Unit/Domain/FormElements/AbstractSectionTest.php
index 12235b346d414d8dacd266a17f557495083d90bb..1fa0f5a59469ef7b6ea0d7ed5068a0d1c14767e5 100644
--- a/typo3/sysext/form/Tests/Unit/Domain/FormElements/AbstractSectionTest.php
+++ b/typo3/sysext/form/Tests/Unit/Domain/FormElements/AbstractSectionTest.php
@@ -33,7 +33,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class AbstractSectionTest extends UnitTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/form/Tests/Unit/Domain/Renderable/RenderableVariantTest.php b/typo3/sysext/form/Tests/Unit/Domain/Renderable/RenderableVariantTest.php
index bbe2471b429f014d995a8cb9271d652bb967e8e4..aa0605c37dc9acf7eb984f5f8a9e95111331203e 100644
--- a/typo3/sysext/form/Tests/Unit/Domain/Renderable/RenderableVariantTest.php
+++ b/typo3/sysext/form/Tests/Unit/Domain/Renderable/RenderableVariantTest.php
@@ -29,7 +29,7 @@ class RenderableVariantTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Set up
diff --git a/typo3/sysext/form/Tests/Unit/Domain/Runtime/FormRuntimeTest.php b/typo3/sysext/form/Tests/Unit/Domain/Runtime/FormRuntimeTest.php
index a9c60f670bb3e9e36b0539a40f080249ed9369d8..66248280749617b92ac619558d009851162dc685 100644
--- a/typo3/sysext/form/Tests/Unit/Domain/Runtime/FormRuntimeTest.php
+++ b/typo3/sysext/form/Tests/Unit/Domain/Runtime/FormRuntimeTest.php
@@ -34,7 +34,7 @@ class FormRuntimeTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/form/Tests/Unit/Hooks/DataStructureIdentifierHookTest.php b/typo3/sysext/form/Tests/Unit/Hooks/DataStructureIdentifierHookTest.php
index 41ae198366818168f173c0ce24a01d9b09be1d76..bbacf228a777ac4842543eb83318223d6ec17407 100644
--- a/typo3/sysext/form/Tests/Unit/Hooks/DataStructureIdentifierHookTest.php
+++ b/typo3/sysext/form/Tests/Unit/Hooks/DataStructureIdentifierHookTest.php
@@ -35,7 +35,7 @@ class DataStructureIdentifierHookTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Set up
diff --git a/typo3/sysext/form/Tests/Unit/Mvc/Configuration/YamlSourceTest.php b/typo3/sysext/form/Tests/Unit/Mvc/Configuration/YamlSourceTest.php
index 0ab9fe05fa97838269c0728e36f860ddb636d7a8..0f5bfcd197d51bd376c842094cad10733014138b 100644
--- a/typo3/sysext/form/Tests/Unit/Mvc/Configuration/YamlSourceTest.php
+++ b/typo3/sysext/form/Tests/Unit/Mvc/Configuration/YamlSourceTest.php
@@ -27,7 +27,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class YamlSourceTest extends UnitTestCase
 {
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/form/Tests/Unit/Mvc/Property/PropertyMappingConfigurationTest.php b/typo3/sysext/form/Tests/Unit/Mvc/Property/PropertyMappingConfigurationTest.php
index de47ea6170adf120e5a4554f84eb2743df179673..e9954b2b1302280b75ad55248cd8bd3d07f9d75f 100644
--- a/typo3/sysext/form/Tests/Unit/Mvc/Property/PropertyMappingConfigurationTest.php
+++ b/typo3/sysext/form/Tests/Unit/Mvc/Property/PropertyMappingConfigurationTest.php
@@ -38,7 +38,7 @@ class PropertyMappingConfigurationTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /** @var PropertyMappingConfiguration */
     protected $propertyMappingConfiguration;
diff --git a/typo3/sysext/form/Tests/Unit/Mvc/Property/TypeConverter/FormDefinitionArrayConverterTest.php b/typo3/sysext/form/Tests/Unit/Mvc/Property/TypeConverter/FormDefinitionArrayConverterTest.php
index f4ccf06254a8675ec7b063f59787b13131d9c853..8997d0934b52577eb0174f72745f2f9d30453208 100644
--- a/typo3/sysext/form/Tests/Unit/Mvc/Property/TypeConverter/FormDefinitionArrayConverterTest.php
+++ b/typo3/sysext/form/Tests/Unit/Mvc/Property/TypeConverter/FormDefinitionArrayConverterTest.php
@@ -34,7 +34,7 @@ class FormDefinitionArrayConverterTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Set up
diff --git a/typo3/sysext/form/Tests/Unit/Service/TranslationServiceTest.php b/typo3/sysext/form/Tests/Unit/Service/TranslationServiceTest.php
index b0f9b78fc8b72d7e9d6bba5180bca64f6779bfc1..09f1c125c66c0c884956f79efa02603ec1134bfc 100644
--- a/typo3/sysext/form/Tests/Unit/Service/TranslationServiceTest.php
+++ b/typo3/sysext/form/Tests/Unit/Service/TranslationServiceTest.php
@@ -43,7 +43,7 @@ class TranslationServiceTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var ConfigurationManager
diff --git a/typo3/sysext/frontend/Tests/Unit/Authentication/FrontendUserAuthenticationTest.php b/typo3/sysext/frontend/Tests/Unit/Authentication/FrontendUserAuthenticationTest.php
index f55af17fdbd08761f30fc8b72e6b7e48e40b0b89..fd5e1a1415346cb59b120635939190b74f527da4 100644
--- a/typo3/sysext/frontend/Tests/Unit/Authentication/FrontendUserAuthenticationTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/Authentication/FrontendUserAuthenticationTest.php
@@ -54,7 +54,7 @@ class FrontendUserAuthenticationTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * User properties should not be set for anonymous sessions
diff --git a/typo3/sysext/frontend/Tests/Unit/ContentObject/CaseContentObjectTest.php b/typo3/sysext/frontend/Tests/Unit/ContentObject/CaseContentObjectTest.php
index 6e649ceccb4140a67fd3620f90e0403454e92b34..70fd30495c11b7f7621d6262ff26ebddfbafdbe0 100644
--- a/typo3/sysext/frontend/Tests/Unit/ContentObject/CaseContentObjectTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/ContentObject/CaseContentObjectTest.php
@@ -35,7 +35,7 @@ class CaseContentObjectTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var CaseContentObject
diff --git a/typo3/sysext/frontend/Tests/Unit/ContentObject/ContentObjectRendererTest.php b/typo3/sysext/frontend/Tests/Unit/ContentObject/ContentObjectRendererTest.php
index 61f49bee045b1293511ac6a7e46ddf8062d3789f..b101d5cc9369247ea63cb060d4a68edbe4ee50bf 100644
--- a/typo3/sysext/frontend/Tests/Unit/ContentObject/ContentObjectRendererTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/ContentObject/ContentObjectRendererTest.php
@@ -91,7 +91,7 @@ class ContentObjectRendererTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var MockObject|AccessibleObjectInterface|ContentObjectRenderer
@@ -139,7 +139,7 @@ class ContentObjectRendererTest extends UnitTestCase
      */
     protected ObjectProphecy $cacheManager;
 
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * Set up
diff --git a/typo3/sysext/frontend/Tests/Unit/ContentObject/Exception/ProductionExceptionHandlerTest.php b/typo3/sysext/frontend/Tests/Unit/ContentObject/Exception/ProductionExceptionHandlerTest.php
index a31f3ae884ffa215a1d9a383759204407257c942..5006fdc4f0bc200453d65ac12b8855900dc0e526 100644
--- a/typo3/sysext/frontend/Tests/Unit/ContentObject/Exception/ProductionExceptionHandlerTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/ContentObject/Exception/ProductionExceptionHandlerTest.php
@@ -35,7 +35,7 @@ class ProductionExceptionHandlerTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected ProductionExceptionHandler $subject;
 
diff --git a/typo3/sysext/frontend/Tests/Unit/ContentObject/FilesContentObjectTest.php b/typo3/sysext/frontend/Tests/Unit/ContentObject/FilesContentObjectTest.php
index 25599633c6e092548e3e42b8e7b2b0aae0f14875..3d37d8e6a557570a81f1e9fa44ef114dfb7313c4 100644
--- a/typo3/sysext/frontend/Tests/Unit/ContentObject/FilesContentObjectTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/ContentObject/FilesContentObjectTest.php
@@ -45,7 +45,7 @@ class FilesContentObjectTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var FilesContentObject|MockObject
diff --git a/typo3/sysext/frontend/Tests/Unit/ContentObject/FluidTemplateContentObjectTest.php b/typo3/sysext/frontend/Tests/Unit/ContentObject/FluidTemplateContentObjectTest.php
index 751715f9f8b1ee5e76761dff6429846950deb8da..db2b729a650dde05c5fbac8ae01435f16fea17b0 100644
--- a/typo3/sysext/frontend/Tests/Unit/ContentObject/FluidTemplateContentObjectTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/ContentObject/FluidTemplateContentObjectTest.php
@@ -51,7 +51,7 @@ class FluidTemplateContentObjectTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var FluidTemplateContentObject|MockObject|AccessibleObjectInterface
diff --git a/typo3/sysext/frontend/Tests/Unit/ContentObject/ImageContentObjectTest.php b/typo3/sysext/frontend/Tests/Unit/ContentObject/ImageContentObjectTest.php
index a73a973765d855d58e46ecdfa4f80ccb0ed882ad..05f3f6c20aa6af7b2b9b170cc64a32a070c36069 100644
--- a/typo3/sysext/frontend/Tests/Unit/ContentObject/ImageContentObjectTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/ContentObject/ImageContentObjectTest.php
@@ -35,7 +35,7 @@ class ImageContentObjectTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var ImageContentObject|MockObject
diff --git a/typo3/sysext/frontend/Tests/Unit/Controller/ErrorControllerTest.php b/typo3/sysext/frontend/Tests/Unit/Controller/ErrorControllerTest.php
index 066945ee83d31ce204791619080684edb68e67cb..e8b4456d5f9f7596e7421b8ed9b7ed2865094821 100644
--- a/typo3/sysext/frontend/Tests/Unit/Controller/ErrorControllerTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/Controller/ErrorControllerTest.php
@@ -30,7 +30,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
 class ErrorControllerTest extends UnitTestCase
 {
     use ProphecyTrait;
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/frontend/Tests/Unit/Controller/TypoScriptFrontendControllerTest.php b/typo3/sysext/frontend/Tests/Unit/Controller/TypoScriptFrontendControllerTest.php
index 386db9523724c8058a088b935a5f96817ce73d1e..656254f662472ffc28a3491f15f59ee499788ec5 100644
--- a/typo3/sysext/frontend/Tests/Unit/Controller/TypoScriptFrontendControllerTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/Controller/TypoScriptFrontendControllerTest.php
@@ -60,7 +60,7 @@ class TypoScriptFrontendControllerTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var MockObject|AccessibleObjectInterface|TypoScriptFrontendController
diff --git a/typo3/sysext/frontend/Tests/Unit/Http/RequestHandlerTest.php b/typo3/sysext/frontend/Tests/Unit/Http/RequestHandlerTest.php
index 336f18550f247e08551f1ddfaaf0a26a59a1dfcd..bd3b42de9a9463cb8dbb27fd9a538eef7ce3c3c3 100644
--- a/typo3/sysext/frontend/Tests/Unit/Http/RequestHandlerTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/Http/RequestHandlerTest.php
@@ -41,7 +41,7 @@ class RequestHandlerTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     public function generateHtmlTagIncludesAllPossibilitiesDataProvider(): array
     {
diff --git a/typo3/sysext/frontend/Tests/Unit/Middleware/PageArgumentValidatorTest.php b/typo3/sysext/frontend/Tests/Unit/Middleware/PageArgumentValidatorTest.php
index 6f143d711d2e2132bbbb118685b4d077bd1e4f33..42c5a45291f220c0dbd89e5569527f83d92079f6 100644
--- a/typo3/sysext/frontend/Tests/Unit/Middleware/PageArgumentValidatorTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/Middleware/PageArgumentValidatorTest.php
@@ -38,7 +38,7 @@ class PageArgumentValidatorTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected CacheHashCalculator $cacheHashCalculator;
     protected TimeTracker $timeTrackerStub;
diff --git a/typo3/sysext/frontend/Tests/Unit/Middleware/PageResolverTest.php b/typo3/sysext/frontend/Tests/Unit/Middleware/PageResolverTest.php
index 253af25bafbca9d59649c551804cfc408721a6f3..7b98d57d63eec1537361cc37b05386ced595fd15 100644
--- a/typo3/sysext/frontend/Tests/Unit/Middleware/PageResolverTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/Middleware/PageResolverTest.php
@@ -40,7 +40,7 @@ class PageResolverTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var TypoScriptFrontendController|AccessibleObjectInterface
diff --git a/typo3/sysext/frontend/Tests/Unit/Middleware/SiteBaseRedirectResolverTest.php b/typo3/sysext/frontend/Tests/Unit/Middleware/SiteBaseRedirectResolverTest.php
index 3290c157db51516cf681a7882436e61c59325307..8e79af1eb1f34b369511349273ce98d5b8a7760a 100644
--- a/typo3/sysext/frontend/Tests/Unit/Middleware/SiteBaseRedirectResolverTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/Middleware/SiteBaseRedirectResolverTest.php
@@ -36,7 +36,7 @@ class SiteBaseRedirectResolverTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected RequestHandlerInterface $siteFoundRequestHandler;
 
diff --git a/typo3/sysext/frontend/Tests/Unit/Middleware/SiteResolverTest.php b/typo3/sysext/frontend/Tests/Unit/Middleware/SiteResolverTest.php
index ae02f145f59c6a978a12c994fdc120363014866e..697911c0b0ca39f25a62805f08ac2277ed96355d 100644
--- a/typo3/sysext/frontend/Tests/Unit/Middleware/SiteResolverTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/Middleware/SiteResolverTest.php
@@ -41,7 +41,7 @@ class SiteResolverTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var SiteFinder|AccessibleObjectInterface
diff --git a/typo3/sysext/frontend/Tests/Unit/Plugin/AbstractPluginTest.php b/typo3/sysext/frontend/Tests/Unit/Plugin/AbstractPluginTest.php
index e239127488cc706b9bfa1fabe9e8fb550069360b..75f94efbf1ef8463ac42aaf08d475376455e4511 100644
--- a/typo3/sysext/frontend/Tests/Unit/Plugin/AbstractPluginTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/Plugin/AbstractPluginTest.php
@@ -42,7 +42,7 @@ class AbstractPluginTest extends UnitTestCase
     /**
      * @var bool
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * Sets up this testcase
diff --git a/typo3/sysext/frontend/Tests/Unit/Resource/FilePathSanitizerTest.php b/typo3/sysext/frontend/Tests/Unit/Resource/FilePathSanitizerTest.php
index c72a87bda9f28012b124729d0c4e80ed0958876b..e559d5a8abdedd2e9318a27cd3ca749adb1b87c1 100644
--- a/typo3/sysext/frontend/Tests/Unit/Resource/FilePathSanitizerTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/Resource/FilePathSanitizerTest.php
@@ -29,7 +29,7 @@ use TYPO3\TestingFramework\Core\Unit\UnitTestCase;
  */
 class FilePathSanitizerTest extends UnitTestCase
 {
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * Sets up Environment to simulate Composer mode and a frontend web request
diff --git a/typo3/sysext/frontend/Tests/Unit/Typolink/AbstractTypolinkBuilderTest.php b/typo3/sysext/frontend/Tests/Unit/Typolink/AbstractTypolinkBuilderTest.php
index fba852e2c3d654958c13b06d3d8562779abe571c..4f2336f521332100da1bd7ea74c9192a000c441e 100644
--- a/typo3/sysext/frontend/Tests/Unit/Typolink/AbstractTypolinkBuilderTest.php
+++ b/typo3/sysext/frontend/Tests/Unit/Typolink/AbstractTypolinkBuilderTest.php
@@ -39,12 +39,12 @@ class AbstractTypolinkBuilderTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var bool Restore Environment after tests
      */
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * @var MockObject|TypoScriptFrontendController|AccessibleObjectInterface
diff --git a/typo3/sysext/frontend/Tests/UnitDeprecated/ContentObject/ContentObjectRendererTest.php b/typo3/sysext/frontend/Tests/UnitDeprecated/ContentObject/ContentObjectRendererTest.php
index e0ac3423d59d2bb624d008fffb34c7052feef5a3..dff8631cc6ca482e907c9ed369ba08281550b647 100644
--- a/typo3/sysext/frontend/Tests/UnitDeprecated/ContentObject/ContentObjectRendererTest.php
+++ b/typo3/sysext/frontend/Tests/UnitDeprecated/ContentObject/ContentObjectRendererTest.php
@@ -64,7 +64,7 @@ class ContentObjectRendererTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var \PHPUnit\Framework\MockObject\MockObject|AccessibleObjectInterface|ContentObjectRenderer
@@ -113,7 +113,7 @@ class ContentObjectRendererTest extends UnitTestCase
      */
     private $cacheManager;
 
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * Set up
diff --git a/typo3/sysext/impexp/Tests/Unit/ExportTest.php b/typo3/sysext/impexp/Tests/Unit/ExportTest.php
index dec654defba50fcd3fbd777c62115ce7c6887895..4105b5e77a79edf799a3e568ff31b01c004fb971 100644
--- a/typo3/sysext/impexp/Tests/Unit/ExportTest.php
+++ b/typo3/sysext/impexp/Tests/Unit/ExportTest.php
@@ -29,7 +29,7 @@ class ExportTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var Export|MockObject|AccessibleObjectInterface
diff --git a/typo3/sysext/indexed_search/Tests/Unit/IndexerTest.php b/typo3/sysext/indexed_search/Tests/Unit/IndexerTest.php
index 98bd3942d0b51bba0b03c572d587c5d947906b9f..f6bb3ca16511da8d9d110750825cfe756cd9bc0f 100644
--- a/typo3/sysext/indexed_search/Tests/Unit/IndexerTest.php
+++ b/typo3/sysext/indexed_search/Tests/Unit/IndexerTest.php
@@ -33,7 +33,7 @@ class IndexerTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     protected function setUp(): void
     {
diff --git a/typo3/sysext/install/Tests/Unit/Service/CoreVersionServiceTest.php b/typo3/sysext/install/Tests/Unit/Service/CoreVersionServiceTest.php
index 7ea5e7fea76eebad0a98535278c3b8d7d0f8151c..e1d7deaf5d8fec7f9bf829e8398139fb6c8d486c 100644
--- a/typo3/sysext/install/Tests/Unit/Service/CoreVersionServiceTest.php
+++ b/typo3/sysext/install/Tests/Unit/Service/CoreVersionServiceTest.php
@@ -38,7 +38,7 @@ class CoreVersionServiceTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     public function setUpApiResponse(string $url, array $responseData): void
     {
diff --git a/typo3/sysext/install/Tests/Unit/Service/EnableFileServiceTest.php b/typo3/sysext/install/Tests/Unit/Service/EnableFileServiceTest.php
index 6ec5d4bf2a63b150188c6b7e6ff9b2b802ff8e19..881e3024ffc531bdff546d3e987e577468381dc2 100644
--- a/typo3/sysext/install/Tests/Unit/Service/EnableFileServiceTest.php
+++ b/typo3/sysext/install/Tests/Unit/Service/EnableFileServiceTest.php
@@ -32,7 +32,7 @@ class EnableFileServiceTest extends UnitTestCase
     /**
      * @var bool This test fiddles with Environment
      */
-    protected $backupEnvironment = true;
+    protected bool $backupEnvironment = true;
 
     /**
      * Data provider
diff --git a/typo3/sysext/redirects/Tests/Functional/Service/IntegrityServiceTest.php b/typo3/sysext/redirects/Tests/Functional/Service/IntegrityServiceTest.php
index 0283eba1d414535376b85f5123df0d439f49b5bf..7ae16f77f06c76c3a24e6ba1237309f2e5b895db 100644
--- a/typo3/sysext/redirects/Tests/Functional/Service/IntegrityServiceTest.php
+++ b/typo3/sysext/redirects/Tests/Functional/Service/IntegrityServiceTest.php
@@ -33,7 +33,7 @@ class IntegrityServiceTest extends FunctionalTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var array
diff --git a/typo3/sysext/redirects/Tests/Unit/Service/RedirectServiceTest.php b/typo3/sysext/redirects/Tests/Unit/Service/RedirectServiceTest.php
index 0c57e9fa7f7cd971fc7d7894c047002955471df3..acf7eeca95a024c122682f3aa09998fff767800e 100644
--- a/typo3/sysext/redirects/Tests/Unit/Service/RedirectServiceTest.php
+++ b/typo3/sysext/redirects/Tests/Unit/Service/RedirectServiceTest.php
@@ -42,7 +42,7 @@ class RedirectServiceTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var RedirectCacheService|ObjectProphecy
diff --git a/typo3/sysext/scheduler/Tests/Unit/Task/CachingFrameworkGarbageCollectionTest.php b/typo3/sysext/scheduler/Tests/Unit/Task/CachingFrameworkGarbageCollectionTest.php
index 17b7945e04355859ef3ea6104cd3c2d3948aee06..60c68bc3d8c3718c76d6ee5c2b12bebf0392a843 100644
--- a/typo3/sysext/scheduler/Tests/Unit/Task/CachingFrameworkGarbageCollectionTest.php
+++ b/typo3/sysext/scheduler/Tests/Unit/Task/CachingFrameworkGarbageCollectionTest.php
@@ -34,7 +34,7 @@ class CachingFrameworkGarbageCollectionTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @test
diff --git a/typo3/sysext/seo/Tests/Unit/XmlSitemap/PagesXmlSitemapDataProviderTest.php b/typo3/sysext/seo/Tests/Unit/XmlSitemap/PagesXmlSitemapDataProviderTest.php
index 5435d457a0ee5227afe76fa0564766b868357757..8f3fb3470ad826c63bff965d27bed3817bf8264e 100644
--- a/typo3/sysext/seo/Tests/Unit/XmlSitemap/PagesXmlSitemapDataProviderTest.php
+++ b/typo3/sysext/seo/Tests/Unit/XmlSitemap/PagesXmlSitemapDataProviderTest.php
@@ -27,7 +27,7 @@ class PagesXmlSitemapDataProviderTest extends UnitTestCase
 {
     use ProphecyTrait;
 
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var array
diff --git a/typo3/sysext/workspaces/Tests/Unit/Controller/Remote/RemoteServerTest.php b/typo3/sysext/workspaces/Tests/Unit/Controller/Remote/RemoteServerTest.php
index eaee3aa96db8a22b446186c86625578d8581b95e..1cceedb385cce052cdb39b0cfaad553904b65920 100644
--- a/typo3/sysext/workspaces/Tests/Unit/Controller/Remote/RemoteServerTest.php
+++ b/typo3/sysext/workspaces/Tests/Unit/Controller/Remote/RemoteServerTest.php
@@ -37,7 +37,7 @@ class RemoteServerTest extends UnitTestCase
     /**
      * @var bool Reset singletons created by subject
      */
-    protected $resetSingletonInstances = true;
+    protected bool $resetSingletonInstances = true;
 
     /**
      * @var FileReference[]|ObjectProphecy[]