diff --git a/core/modules/filter/tests/src/Unit/FilterUninstallValidatorTest.php b/core/modules/filter/tests/src/Unit/FilterUninstallValidatorTest.php
index b3319192cc60135d7d3b638e0c5d745f83b55322..85fcbe3184866a169d84b7e2035f7da911fb5a3e 100644
--- a/core/modules/filter/tests/src/Unit/FilterUninstallValidatorTest.php
+++ b/core/modules/filter/tests/src/Unit/FilterUninstallValidatorTest.php
@@ -4,6 +4,8 @@
 
 namespace Drupal\Tests\filter\Unit;
 
+use Drupal\filter\FilterProcessResult;
+use Drupal\filter\Plugin\FilterBase;
 use Drupal\Tests\UnitTestCase;
 
 /**
@@ -92,8 +94,8 @@ public function testValidateNoMatchingFormats() {
         ],
       ]);
 
-    $filter_plugin_enabled = $this->getMockForAbstractClass('Drupal\filter\Plugin\FilterBase', [['status' => TRUE], '', ['provider' => 'filter_test']]);
-    $filter_plugin_disabled = $this->getMockForAbstractClass('Drupal\filter\Plugin\FilterBase', [['status' => FALSE], '', ['provider' => 'filter_test']]);
+    $filter_plugin_enabled = new FilterBaseTestableClass(['status' => TRUE], '', ['provider' => 'filter_test']);
+    $filter_plugin_disabled = new FilterBaseTestableClass(['status' => FALSE], '', ['provider' => 'filter_test']);
 
     // The first format has 2 matching and enabled filters, but the loop breaks
     // after finding the first one.
@@ -163,3 +165,14 @@ public function testValidateNoMatchingFormats() {
   }
 
 }
+
+/**
+ * A class extending FilterBase for testing purposes.
+ */
+class FilterBaseTestableClass extends FilterBase {
+
+  public function process($text, $langcode) {
+    return new FilterProcessResult();
+  }
+
+}
diff --git a/core/tests/Drupal/Tests/Core/Config/Entity/ConfigEntityBaseUnitTest.php b/core/tests/Drupal/Tests/Core/Config/Entity/ConfigEntityBaseUnitTest.php
index fffbee4f8f0873eb2dc1e128280f8acba17df8c4..35316ac0dcf501a3ec2e354a5263648fd4841776 100644
--- a/core/tests/Drupal/Tests/Core/Config/Entity/ConfigEntityBaseUnitTest.php
+++ b/core/tests/Drupal/Tests/Core/Config/Entity/ConfigEntityBaseUnitTest.php
@@ -160,7 +160,10 @@ protected function setUp(): void {
     $container->set('theme_handler', $this->themeHandler->reveal());
     \Drupal::setContainer($container);
 
-    $this->entity = $this->getMockForAbstractClass('\Drupal\Core\Config\Entity\ConfigEntityBase', [$values, $this->entityTypeId]);
+    $this->entity = $this->getMockBuilder(ConfigEntityBaseMockableClass::class)
+      ->setConstructorArgs([$values, $this->entityTypeId])
+      ->onlyMethods([])
+      ->getMock();
   }
 
   /**
@@ -332,7 +335,10 @@ public static function providerCalculateDependenciesWithPluginCollections(): arr
    * @covers ::onDependencyRemoval
    */
   public function testCalculateDependenciesWithThirdPartySettings() {
-    $this->entity = $this->getMockForAbstractClass('\Drupal\Core\Config\Entity\ConfigEntityBase', [[], $this->entityTypeId]);
+    $this->entity = $this->getMockBuilder(ConfigEntityBaseMockableClass::class)
+      ->setConstructorArgs([[], $this->entityTypeId])
+      ->onlyMethods([])
+      ->getMock();
     $this->entity->setThirdPartySetting('test_provider', 'test', 'test');
     $this->entity->setThirdPartySetting('test_provider2', 'test', 'test');
     $this->entity->setThirdPartySetting(static::PROVIDER, 'test', 'test');
@@ -564,7 +570,10 @@ public function testToArray() {
    * @covers ::toArray
    */
   public function testToArrayIdKey() {
-    $entity = $this->getMockForAbstractClass('\Drupal\Core\Config\Entity\ConfigEntityBase', [[], $this->entityTypeId], '', TRUE, TRUE, TRUE, ['id', 'get']);
+    $entity = $this->getMockBuilder(ConfigEntityBaseMockableClass::class)
+      ->setConstructorArgs([[], $this->entityTypeId])
+      ->onlyMethods(['id', 'get'])
+      ->getMock();
     $entity->expects($this->atLeastOnce())
       ->method('id')
       ->willReturn($this->id);
@@ -739,3 +748,10 @@ public function getPluginCollections() {
   }
 
 }
+
+/**
+ * A class extending ConfigEntityBase for testing purposes.
+ */
+class ConfigEntityBaseMockableClass extends ConfigEntityBase {
+
+}
diff --git a/core/tests/Drupal/Tests/Core/Config/Entity/EntityDisplayBaseTest.php b/core/tests/Drupal/Tests/Core/Config/Entity/EntityDisplayBaseTest.php
index 13163a10828e508a23c4798edca9a2b89998d069..010bc319174c5d7a8b940839dbe99ae31be126ba 100644
--- a/core/tests/Drupal/Tests/Core/Config/Entity/EntityDisplayBaseTest.php
+++ b/core/tests/Drupal/Tests/Core/Config/Entity/EntityDisplayBaseTest.php
@@ -4,7 +4,9 @@
 
 namespace Drupal\Tests\Core\Config\Entity;
 
+use Drupal\Core\Entity\EntityDisplayBase;
 use Drupal\Tests\UnitTestCase;
+use PHPUnit\Framework\MockObject\MockObject;
 
 /**
  * @coversDefaultClass \Drupal\Core\Entity\EntityDisplayBase
@@ -13,54 +15,80 @@
  */
 class EntityDisplayBaseTest extends UnitTestCase {
 
+  /**
+   * The mocked EntityDisplay object for testing.
+   */
+  protected EntityDisplayBaseMockableClass&MockObject $entityDisplay;
+
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp(): void {
+    parent::setUp();
+    $this->entityDisplay = $this->getMockBuilder(EntityDisplayBaseMockableClass::class)
+      ->disableOriginalConstructor()
+      ->onlyMethods([])
+      ->getMock();
+  }
+
   /**
    * @covers ::getTargetEntityTypeId
    */
   public function testGetTargetEntityTypeId() {
-    $mock = $this->getMockForAbstractClass('\Drupal\Core\Entity\EntityDisplayBase', [], '', FALSE);
-    $reflection = new \ReflectionProperty($mock, 'targetEntityType');
-    $reflection->setValue($mock, 'test');
-    $this->assertEquals('test', $mock->getTargetEntityTypeId());
+    $reflection = new \ReflectionProperty($this->entityDisplay, 'targetEntityType');
+    $reflection->setValue($this->entityDisplay, 'test');
+    $this->assertEquals('test', $this->entityDisplay->getTargetEntityTypeId());
   }
 
   /**
    * @covers ::getMode
    */
   public function testGetMode() {
-    $mock = $this->getMockForAbstractClass('\Drupal\Core\Entity\EntityDisplayBase', [], '', FALSE);
-    $reflection = new \ReflectionProperty($mock, 'mode');
-    $reflection->setValue($mock, 'test');
-    $this->assertEquals('test', $mock->getMode());
+    $reflection = new \ReflectionProperty($this->entityDisplay, 'mode');
+    $reflection->setValue($this->entityDisplay, 'test');
+    $this->assertEquals('test', $this->entityDisplay->getMode());
   }
 
   /**
    * @covers ::getOriginalMode
    */
   public function testGetOriginalMode() {
-    $mock = $this->getMockForAbstractClass('\Drupal\Core\Entity\EntityDisplayBase', [], '', FALSE);
-    $reflection = new \ReflectionProperty($mock, 'originalMode');
-    $reflection->setValue($mock, 'test');
-    $this->assertEquals('test', $mock->getOriginalMode());
+    $reflection = new \ReflectionProperty($this->entityDisplay, 'originalMode');
+    $reflection->setValue($this->entityDisplay, 'test');
+    $this->assertEquals('test', $this->entityDisplay->getOriginalMode());
   }
 
   /**
    * @covers ::getTargetBundle
    */
   public function testGetTargetBundle() {
-    $mock = $this->getMockForAbstractClass('\Drupal\Core\Entity\EntityDisplayBase', [], '', FALSE);
-    $reflection = new \ReflectionProperty($mock, 'bundle');
-    $reflection->setValue($mock, 'test');
-    $this->assertEquals('test', $mock->getTargetBundle());
+    $reflection = new \ReflectionProperty($this->entityDisplay, 'bundle');
+    $reflection->setValue($this->entityDisplay, 'test');
+    $this->assertEquals('test', $this->entityDisplay->getTargetBundle());
   }
 
   /**
    * @covers ::setTargetBundle
    */
   public function testSetTargetBundle() {
-    $mock = $this->getMockForAbstractClass('\Drupal\Core\Entity\EntityDisplayBase', [], '', FALSE);
-    $reflection = new \ReflectionProperty($mock, 'bundle');
-    $mock->setTargetBundle('test');
-    $this->assertEquals('test', $reflection->getValue($mock));
+    $reflection = new \ReflectionProperty($this->entityDisplay, 'bundle');
+    $this->entityDisplay->setTargetBundle('test');
+    $this->assertEquals('test', $reflection->getValue($this->entityDisplay));
+  }
+
+}
+
+/**
+ * A class extending EntityDisplayBase for testing purposes.
+ */
+class EntityDisplayBaseMockableClass extends EntityDisplayBase {
+
+  public function getPluginCollections() {
+    return [];
+  }
+
+  public function getRenderer($field_name) {
+    return NULL;
   }
 
 }
diff --git a/core/tests/Drupal/Tests/Core/Test/BrowserTestBaseTest.php b/core/tests/Drupal/Tests/Core/Test/BrowserTestBaseTest.php
index 80f325231ebc3af291eaf9e802a9c32c42cee5f4..db5d7c0e7e04f21453346f77c378758902ec2330 100644
--- a/core/tests/Drupal/Tests/Core/Test/BrowserTestBaseTest.php
+++ b/core/tests/Drupal/Tests/Core/Test/BrowserTestBaseTest.php
@@ -26,10 +26,10 @@ protected function mockBrowserTestBaseWithDriver($driver) {
       ->method('getDriver')
       ->willReturn($driver);
 
-    $btb = $this->getMockBuilder(BrowserTestBase::class)
+    $btb = $this->getMockBuilder(BrowserTestBaseMockableClass::class)
       ->disableOriginalConstructor()
       ->onlyMethods(['getSession'])
-      ->getMockForAbstractClass();
+      ->getMock();
     $btb->expects($this->any())
       ->method('getSession')
       ->willReturn($session);
@@ -46,7 +46,7 @@ public function testGetHttpClient() {
 
     $browserkit_client = $this->getMockBuilder(DrupalTestBrowser::class)
       ->onlyMethods(['getClient'])
-      ->getMockForAbstractClass();
+      ->getMock();
     $browserkit_client->expects($this->once())
       ->method('getClient')
       ->willReturn($expected);
@@ -83,10 +83,10 @@ public function testGetHttpClientException() {
   public function testTearDownWithoutSetUp() {
     $method = 'cleanupEnvironment';
     $this->assertTrue(method_exists(BrowserTestBase::class, $method));
-    $btb = $this->getMockBuilder(BrowserTestBase::class)
+    $btb = $this->getMockBuilder(BrowserTestBaseMockableClass::class)
       ->disableOriginalConstructor()
       ->onlyMethods([$method])
-      ->getMockForAbstractClass();
+      ->getMock();
     $btb->expects($this->never())->method($method);
     $ref_tearDown = new \ReflectionMethod($btb, 'tearDown');
     $ref_tearDown->invoke($btb);
@@ -106,3 +106,10 @@ public function testGetRandomGeneratorPropertyDeprecation() {
   }
 
 }
+
+/**
+ * A class extending BrowserTestBase for testing purposes.
+ */
+class BrowserTestBaseMockableClass extends BrowserTestBase {
+
+}
diff --git a/core/tests/Drupal/Tests/Core/Test/WebDriverTestBaseTest.php b/core/tests/Drupal/Tests/Core/Test/WebDriverTestBaseTest.php
index d457f21e81e7a7efb044a8ad2d627e5247e26089..4fa6d8c76a0a8454d5a2177569607515d1928c4d 100644
--- a/core/tests/Drupal/Tests/Core/Test/WebDriverTestBaseTest.php
+++ b/core/tests/Drupal/Tests/Core/Test/WebDriverTestBaseTest.php
@@ -31,7 +31,8 @@ public function testCapabilities($expected, ?string $mink_driver_args_webdriver,
     $this->putEnv("MINK_DRIVER_ARGS_WEBDRIVER", $mink_driver_args_webdriver);
     $this->putEnv("MINK_DRIVER_ARGS", $mink_driver_args);
 
-    $object = $this->getMockForAbstractClass(WebDriverTestBase::class);
+    $object = new class('test') extends WebDriverTestBase {
+    };
     $method = new \ReflectionMethod($object, 'getMinkDriverArgs');
     $this->assertSame($expected, $method->invoke($object));
   }
@@ -67,7 +68,8 @@ public function testChromeOptions(): void {
     $this->expectDeprecation('The "chromeOptions" array key is deprecated in drupal:10.3.0 and is removed from drupal:11.0.0. Use "goog:chromeOptions instead. See https://www.drupal.org/node/3422624');
     putenv('MINK_DRIVER_ARGS_WEBDRIVER=["chrome",{"browserName":"chrome","chromeOptions":{"args":["--headless"]}},"http://localhost:4444"]');
 
-    $object = $this->getMockForAbstractClass(WebDriverTestBase::class);
+    $object = new class('test') extends WebDriverTestBase {
+    };
     $method = new \ReflectionMethod($object, 'getMinkDriverArgs');
     $this->assertSame('["chrome",{"browserName":"chrome","goog:chromeOptions":{"args":["--headless"],"w3c":false}},"http:\\/\\/localhost:4444"]', $method->invoke($object));
   }