diff --git a/core/modules/announcements_feed/tests/src/FunctionalJavascript/AlertsJsonFeedTest.php b/core/modules/announcements_feed/tests/src/FunctionalJavascript/AlertsJsonFeedTest.php
index a4b09d7feaeeeead91cae51d7cf2ecad75f6a019..39edf53e90c11b1d6f96156b0e545e7814007b8e 100644
--- a/core/modules/announcements_feed/tests/src/FunctionalJavascript/AlertsJsonFeedTest.php
+++ b/core/modules/announcements_feed/tests/src/FunctionalJavascript/AlertsJsonFeedTest.php
@@ -41,6 +41,10 @@ class AlertsJsonFeedTest extends OffCanvasTestBase {
    * {@inheritdoc}
    */
   public function setUp():void {
+    if ($this->name() === 'testAnnounceFeedUpdatedAndRemoved') {
+      $this->markTestSkipped('Skipped due to major version-specific logic. See https://www.drupal.org/project/drupal/issues/3359322');
+    }
+
     parent::setUp();
 
     $this->user = $this->drupalCreateUser(
@@ -57,7 +61,6 @@ public function setUp():void {
    * Check the status of the announcements when the feed is updated and removed.
    */
   public function testAnnounceFeedUpdatedAndRemoved(): void {
-    $this->markTestSkipped('Skipped due to major version-specific logic. See https://www.drupal.org/project/drupal/issues/3359322');
     $this->drupalLogin($this->user);
     $this->drupalGet('<front>');
     $this->clickLink('Announcements');
diff --git a/core/modules/announcements_feed/tests/src/Kernel/AnnounceFetcherTest.php b/core/modules/announcements_feed/tests/src/Kernel/AnnounceFetcherTest.php
index d2c70ae8d7607146572a2d5612c6e98bd8899a7e..0d144f0878f9b8276c77cda3982e393cd3f2a780 100644
--- a/core/modules/announcements_feed/tests/src/Kernel/AnnounceFetcherTest.php
+++ b/core/modules/announcements_feed/tests/src/Kernel/AnnounceFetcherTest.php
@@ -17,6 +17,7 @@ class AnnounceFetcherTest extends AnnounceTestBase {
    * {@inheritdoc}
    */
   protected function setUp(): void {
+    $this->markTestSkipped('Skipped due to major version-specific logic. See https://www.drupal.org/project/drupal/issues/3359322');
     parent::setUp();
     $this->installConfig(['announcements_feed']);
   }
@@ -31,7 +32,6 @@ protected function setUp(): void {
    * @dataProvider providerShowAnnouncements
    */
   public function testShowAnnouncements(array $feed_item): void {
-    $this->markTestSkipped('Skipped due to major version-specific logic. See https://www.drupal.org/project/drupal/issues/3359322');
     $this->setFeedItems([$feed_item]);
     $feeds = $this->fetchFeedItems();
     $this->assertCount(1, $feeds);
@@ -45,7 +45,6 @@ public function testShowAnnouncements(array $feed_item): void {
    * Tests feed fields.
    */
   public function testFeedFields(): void {
-    $this->markTestSkipped('Skipped due to major version-specific logic. See https://www.drupal.org/project/drupal/issues/3359322');
     $feed_item_1 = [
       'id' => '1001',
       'content_html' => 'Test teaser 1',
diff --git a/core/modules/ckeditor5/tests/src/FunctionalJavascript/MediaLibraryTest.php b/core/modules/ckeditor5/tests/src/FunctionalJavascript/MediaLibraryTest.php
index ccf189d484a27d09bfd143ddf30d6f95ffa97444..c95baf47e0c48ef3173975c86d20f8e80b1884f3 100644
--- a/core/modules/ckeditor5/tests/src/FunctionalJavascript/MediaLibraryTest.php
+++ b/core/modules/ckeditor5/tests/src/FunctionalJavascript/MediaLibraryTest.php
@@ -62,6 +62,10 @@ class MediaLibraryTest extends WebDriverTestBase {
    * {@inheritdoc}
    */
   protected function setUp(): void {
+    if ($this->name() === 'testButton') {
+      $this->markTestSkipped('Skipped due to frequent random test failures. See https://www.drupal.org/i/3351597');
+    }
+
     parent::setUp();
 
     FilterFormat::create([
@@ -156,9 +160,6 @@ function (ConstraintViolationInterface $v) {
    * Tests using drupalMedia button to embed media into CKEditor 5.
    */
   public function testButton(): void {
-    // Skipped due to frequent random test failures.
-    // @todo Fix this and stop skipping it at https://www.drupal.org/i/3351597.
-    $this->markTestSkipped();
     $media_preview_selector = '.ck-content .ck-widget.drupal-media .media';
     $this->drupalGet('/node/add/blog');
     $this->waitForEditor();
diff --git a/core/modules/layout_builder/tests/src/FunctionalJavascript/LayoutBuilderUiTest.php b/core/modules/layout_builder/tests/src/FunctionalJavascript/LayoutBuilderUiTest.php
index 46f15a177c2c6fc938e4628d24578d5971a1b689..a9205d9f0dc383a3fc829331f8e3ed35161dd20c 100644
--- a/core/modules/layout_builder/tests/src/FunctionalJavascript/LayoutBuilderUiTest.php
+++ b/core/modules/layout_builder/tests/src/FunctionalJavascript/LayoutBuilderUiTest.php
@@ -48,6 +48,10 @@ class LayoutBuilderUiTest extends WebDriverTestBase {
    * {@inheritdoc}
    */
   protected function setUp(): void {
+    if ($this->name() === 'testAddHighlights') {
+      $this->markTestSkipped("Skipped temporarily for random fails.");
+    }
+
     parent::setUp();
 
     $this->createContentType(['type' => 'bundle_with_section_field']);
@@ -299,7 +303,6 @@ private function assertHighlightedElement(string $selector): void {
    * Waits for the dialog to close and confirms no highlights are present.
    */
   private function assertHighlightNotExists(): void {
-    $this->markTestSkipped("Skipped temporarily for random fails.");
     $assert_session = $this->assertSession();
 
     $assert_session->assertNoElementAfterWait('css', '#drupal-off-canvas');
diff --git a/core/modules/layout_builder/tests/src/FunctionalJavascript/MoveBlockFormTest.php b/core/modules/layout_builder/tests/src/FunctionalJavascript/MoveBlockFormTest.php
index ba11617ffae77b1045170e68e9753c4f98c69261..df748df0e0807544b9012dd2b5555036515abeff 100644
--- a/core/modules/layout_builder/tests/src/FunctionalJavascript/MoveBlockFormTest.php
+++ b/core/modules/layout_builder/tests/src/FunctionalJavascript/MoveBlockFormTest.php
@@ -39,6 +39,8 @@ class MoveBlockFormTest extends WebDriverTestBase {
    * {@inheritdoc}
    */
   protected function setUp(): void {
+    $this->markTestSkipped("Skipped temporarily for random fails.");
+
     parent::setUp();
     $page = $this->getSession()->getPage();
     $assert_session = $this->assertSession();
@@ -66,7 +68,6 @@ protected function setUp(): void {
       '.block-extra-field-blocknodebundle-with-section-fieldlinks',
       '.block-field-blocknodebundle-with-section-fieldbody',
     ];
-    $this->markTestSkipped("Skipped temporarily for random fails.");
     $this->assertRegionBlocksOrder(0, 'content', $expected_block_order);
 
     // Add a top section using the Two column layout.
diff --git a/core/modules/settings_tray/tests/src/FunctionalJavascript/SettingsTrayBlockFormTest.php b/core/modules/settings_tray/tests/src/FunctionalJavascript/SettingsTrayBlockFormTest.php
index 85eb9eadcf1d99b05a5cec293ab9fe1f5049aa3d..26c24424f9d1fd8d1c84882e89462d11b02878a1 100644
--- a/core/modules/settings_tray/tests/src/FunctionalJavascript/SettingsTrayBlockFormTest.php
+++ b/core/modules/settings_tray/tests/src/FunctionalJavascript/SettingsTrayBlockFormTest.php
@@ -34,6 +34,10 @@ class SettingsTrayBlockFormTest extends SettingsTrayTestBase {
    * {@inheritdoc}
    */
   protected function setUp(): void {
+    if ($this->name() === 'testEditModeEnableDisable') {
+      $this->markTestSkipped("Skipped due to frequent random test failures. See https://www.drupal.org/project/drupal/issues/3317520");
+    }
+
     parent::setUp();
 
     $user = $this->createUser([
@@ -231,7 +235,6 @@ public function getBlockTests() {
    * Tests enabling and disabling Edit Mode.
    */
   public function testEditModeEnableDisable(): void {
-    $this->markTestSkipped("Skipped due to frequent random test failures. See https://www.drupal.org/project/drupal/issues/3317520");
     foreach (static::getTestThemes() as $theme) {
       $this->enableTheme($theme);
       $block = $this->placeBlock('system_powered_by_block');
diff --git a/core/modules/system/tests/src/Functional/Module/DependencyTest.php b/core/modules/system/tests/src/Functional/Module/DependencyTest.php
index ef30c4f713ff948254bf9f4119b0cddfe5d18a2c..7f2d218388a884155cdb1254a5a8f20ba411b193 100644
--- a/core/modules/system/tests/src/Functional/Module/DependencyTest.php
+++ b/core/modules/system/tests/src/Functional/Module/DependencyTest.php
@@ -19,6 +19,16 @@ class DependencyTest extends ModuleTestBase {
    */
   protected $defaultTheme = 'stark';
 
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp(): void {
+    if ($this->name() === 'testCoreCompatibility') {
+      $this->markTestSkipped('Skipped due to major version-specific logic. See https://www.drupal.org/project/drupal/issues/3359322');
+    }
+    parent::setUp();
+  }
+
   /**
    * Checks functionality of project namespaces for dependencies.
    */
@@ -173,7 +183,6 @@ public function testIncompatiblePhpVersionDependency(): void {
    * Tests enabling modules with different core version specifications.
    */
   public function testCoreCompatibility(): void {
-    $this->markTestSkipped('Skipped due to major version-specific logic. See https://www.drupal.org/project/drupal/issues/3359322');
     $assert_session = $this->assertSession();
 
     // Test incompatible 'core_version_requirement'.
diff --git a/core/modules/system/tests/src/Functional/System/ThemeTest.php b/core/modules/system/tests/src/Functional/System/ThemeTest.php
index a5fbadec916a84c29e7a266db685771189c663b9..2b91b132371c57cdb8bb0c9edf3fc85761437b5a 100644
--- a/core/modules/system/tests/src/Functional/System/ThemeTest.php
+++ b/core/modules/system/tests/src/Functional/System/ThemeTest.php
@@ -49,6 +49,10 @@ class ThemeTest extends BrowserTestBase {
    * {@inheritdoc}
    */
   protected function setUp(): void {
+    if ($this->name() === 'testInstallAndSetAsDefault') {
+      $this->markTestSkipped('Skipped due to major version-specific logic. See https://www.drupal.org/project/drupal/issues/3359322');
+    }
+
     parent::setUp();
 
     $this->drupalCreateContentType(['type' => 'page', 'name' => 'Basic page']);
@@ -527,7 +531,6 @@ public function testUninstallingThemes(): void {
    * Tests installing a theme and setting it as default.
    */
   public function testInstallAndSetAsDefault(): void {
-    $this->markTestSkipped('Skipped due to major version-specific logic. See https://www.drupal.org/project/drupal/issues/3359322');
     $themes = [
       'olivero' => 'Olivero',
       'test_core_semver' => 'Theme test with semver core version',
diff --git a/core/modules/system/tests/src/Functional/UpdateSystem/UpdateScriptTest.php b/core/modules/system/tests/src/Functional/UpdateSystem/UpdateScriptTest.php
index 210e41e840d5d933908f73159932a0ee0c6fb158..f0f78b23c99ca6d3c264ebbb81512fdf3223332f 100644
--- a/core/modules/system/tests/src/Functional/UpdateSystem/UpdateScriptTest.php
+++ b/core/modules/system/tests/src/Functional/UpdateSystem/UpdateScriptTest.php
@@ -64,6 +64,9 @@ class UpdateScriptTest extends BrowserTestBase {
    * {@inheritdoc}
    */
   protected function setUp(): void {
+    if ($this->name() === 'testMissingExtension') {
+      $this->markTestSkipped('Skipped due to major version-specific logic. See https://www.drupal.org/project/drupal/issues/3359322');
+    }
     parent::setUp();
     $this->updateUrl = Url::fromRoute('system.db_update');
     $this->statusReportUrl = Url::fromRoute('system.status');
@@ -350,7 +353,6 @@ public static function providerExtensionCompatibilityChange() {
    * @dataProvider providerMissingExtension
    */
   public function testMissingExtension(array $core, array $contrib): void {
-    $this->markTestSkipped('Skipped due to major version-specific logic. See https://www.drupal.org/project/drupal/issues/3359322');
     $this->drupalLogin(
       $this->drupalCreateUser(
         [
diff --git a/core/tests/Drupal/FunctionalJavascriptTests/Ajax/AjaxTest.php b/core/tests/Drupal/FunctionalJavascriptTests/Ajax/AjaxTest.php
index 3d056401a2b81aa19bb4c46bdfcd9a1450b76a48..03bd477123c115b8a993b5c00d3abf8e7a963239 100644
--- a/core/tests/Drupal/FunctionalJavascriptTests/Ajax/AjaxTest.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/Ajax/AjaxTest.php
@@ -24,6 +24,16 @@ class AjaxTest extends WebDriverTestBase {
    */
   protected $defaultTheme = 'stark';
 
+  /**
+   * {@inheritdoc}
+   */
+  protected function setUp(): void {
+    if ($this->name() === 'testAjaxFocus') {
+      $this->markTestSkipped("Skipped due to frequent random test failures. See https://www.drupal.org/project/drupal/issues/3396536");
+    }
+    parent::setUp();
+  }
+
   public function testAjaxWithAdminRoute(): void {
     \Drupal::service('theme_installer')->install(['stable9', 'claro']);
     $theme_config = \Drupal::configFactory()->getEditable('system.theme');
@@ -301,7 +311,6 @@ public function testUiAjaxException(): void {
    * Tests ajax focus handling.
    */
   public function testAjaxFocus(): void {
-    $this->markTestSkipped("Skipped due to frequent random test failures. See https://www.drupal.org/project/drupal/issues/3396536");
     $this->drupalGet('/ajax_forms_test_get_form');
 
     $this->assertNotNull($select = $this->assertSession()->elementExists('css', '#edit-select'));
diff --git a/core/tests/Drupal/FunctionalJavascriptTests/Core/Field/TimestampFormatterWithTimeDiffTest.php b/core/tests/Drupal/FunctionalJavascriptTests/Core/Field/TimestampFormatterWithTimeDiffTest.php
index 92ce9180329484de8e03be9d55175b0df84f1565..53b2c5dcb7a546e9b92372741aab18fb7c393501 100644
--- a/core/tests/Drupal/FunctionalJavascriptTests/Core/Field/TimestampFormatterWithTimeDiffTest.php
+++ b/core/tests/Drupal/FunctionalJavascriptTests/Core/Field/TimestampFormatterWithTimeDiffTest.php
@@ -39,6 +39,10 @@ class TimestampFormatterWithTimeDiffTest extends WebDriverTestBase {
    * {@inheritdoc}
    */
   protected function setUp(): void {
+    if ($this->name() === 'testNoRefreshInterval') {
+      $this->markTestSkipped("Skipped due to frequent random test failures. See https://www.drupal.org/project/drupal/issues/3400150");
+    }
+
     parent::setUp();
 
     FieldStorageConfig::create([
@@ -138,7 +142,6 @@ public function testTimestampFormatterWithTimeDiff(): void {
    * Tests the 'timestamp' formatter without refresh interval.
    */
   public function testNoRefreshInterval(): void {
-    $this->markTestSkipped("Skipped due to frequent random test failures. See https://www.drupal.org/project/drupal/issues/3400150");
     // Set the refresh interval to zero, meaning "no refresh".
     $display = EntityViewDisplay::load('entity_test.entity_test.default');
     $component = $display->getComponent('time_field');