diff --git a/Tests/Unit/Domain/Model/FrontendUserGroupTest.php b/Tests/Unit/Domain/Model/FrontendUserGroupTest.php
index be6befc..5c8260d 100644
--- a/Tests/Unit/Domain/Model/FrontendUserGroupTest.php
+++ b/Tests/Unit/Domain/Model/FrontendUserGroupTest.php
@@ -6,7 +6,6 @@
 
 use OliverKlee\FeUserExtraFields\Domain\Model\FrontendUserGroup;
 use OliverKlee\FeUserExtraFields\Tests\Unit\Domain\Model\Fixtures\XclassFrontendUserGroup;
-use OliverKlee\FeUserExtraFields\Tests\Unit\Support\MakeInstanceCacheFlusher;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\CMS\Extbase\DomainObject\AbstractEntity;
 use TYPO3\CMS\Extbase\Persistence\ObjectStorage;
@@ -22,7 +21,7 @@ final class FrontendUserGroupTest extends UnitTestCase
     protected function setUp(): void
     {
         parent::setUp();
-        MakeInstanceCacheFlusher::flushMakeInstanceCache();
+        GeneralUtility::flushInternalRuntimeCaches();
 
         $this->subject = new FrontendUserGroup();
     }
@@ -31,7 +30,7 @@ protected function tearDown(): void
     {
         // @phpstan-ignore offsetAccess.nonOffsetAccessible, offsetAccess.nonOffsetAccessible
         unset($GLOBALS['TYPO3_CONF_VARS']['SYS']['Objects']);
-        MakeInstanceCacheFlusher::flushMakeInstanceCache();
+        GeneralUtility::flushInternalRuntimeCaches();
         parent::tearDown();
     }
 
diff --git a/Tests/Unit/Domain/Model/FrontendUserTest.php b/Tests/Unit/Domain/Model/FrontendUserTest.php
index bd6bb81..954fdbe 100644
--- a/Tests/Unit/Domain/Model/FrontendUserTest.php
+++ b/Tests/Unit/Domain/Model/FrontendUserTest.php
@@ -7,7 +7,6 @@
 use OliverKlee\FeUserExtraFields\Domain\Model\FrontendUser;
 use OliverKlee\FeUserExtraFields\Domain\Model\FrontendUserGroup;
 use OliverKlee\FeUserExtraFields\Tests\Unit\Domain\Model\Fixtures\XclassFrontendUser;
-use OliverKlee\FeUserExtraFields\Tests\Unit\Support\MakeInstanceCacheFlusher;
 use TYPO3\CMS\Core\Utility\GeneralUtility;
 use TYPO3\CMS\Extbase\Domain\Model\FileReference;
 use TYPO3\CMS\Extbase\DomainObject\AbstractEntity;
@@ -24,7 +23,7 @@ final class FrontendUserTest extends UnitTestCase
     protected function setUp(): void
     {
         parent::setUp();
-        MakeInstanceCacheFlusher::flushMakeInstanceCache();
+        GeneralUtility::flushInternalRuntimeCaches();
 
         $this->subject = new FrontendUser();
     }
@@ -33,7 +32,7 @@ protected function tearDown(): void
     {
         // @phpstan-ignore offsetAccess.nonOffsetAccessible, offsetAccess.nonOffsetAccessible
         unset($GLOBALS['TYPO3_CONF_VARS']['SYS']['Objects']);
-        MakeInstanceCacheFlusher::flushMakeInstanceCache();
+        GeneralUtility::flushInternalRuntimeCaches();
         parent::tearDown();
     }
 
diff --git a/Tests/Unit/Support/MakeInstanceCacheFlusher.php b/Tests/Unit/Support/MakeInstanceCacheFlusher.php
deleted file mode 100644
index c14ec5f..0000000
--- a/Tests/Unit/Support/MakeInstanceCacheFlusher.php
+++ /dev/null
@@ -1,24 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace OliverKlee\FeUserExtraFields\Tests\Unit\Support;
-
-use TYPO3\CMS\Core\Utility\GeneralUtility;
-
-/**
- * Class to provide access to protected static members of `GeneralUtility`.
- *
- * @deprecated Replace `GeneralUtlity::flushInternalRuntimeCaches` once we require core versions that have the
- * corresponding patch.
- */
-final class MakeInstanceCacheFlusher extends GeneralUtility
-{
-    /**
-     * Flushes the class name cache for `GeneralUtility::makeInstance()`.
-     */
-    public static function flushMakeInstanceCache(): void
-    {
-        self::$finalClassNameCache = [];
-    }
-}