diff --git a/core/modules/block_content/tests/src/Kernel/Migrate/d6/MigrateBlockContentTest.php b/core/modules/block_content/tests/src/Kernel/Migrate/d6/MigrateBlockContentTest.php
index cd6fc7a12ce39902d3cb089de9d5bba9a82f3a11..50bb3cb1597114715eed888d028e3027c1e12534 100644
--- a/core/modules/block_content/tests/src/Kernel/Migrate/d6/MigrateBlockContentTest.php
+++ b/core/modules/block_content/tests/src/Kernel/Migrate/d6/MigrateBlockContentTest.php
@@ -40,7 +40,8 @@ public function testBlockMigration() {
     /** @var \Drupal\block_content\Entity\BlockContent $block */
     $block = BlockContent::load(1);
     $this->assertSame('My block 1', $block->label());
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $block->getChangedTime());
+    $requestTime = \Drupal::time()->getRequestTime();
+    $this->assertGreaterThanOrEqual($requestTime, (int) $block->getChangedTime());
     $this->assertLessThanOrEqual(time(), $block->getChangedTime());
     $this->assertSame('en', $block->language()->getId());
     $this->assertSame('<h3>My first content block body</h3>', $block->body->value);
@@ -48,7 +49,8 @@ public function testBlockMigration() {
 
     $block = BlockContent::load(2);
     $this->assertSame('My block 2', $block->label());
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $block->getChangedTime());
+    $this->assertGreaterThanOrEqual($requestTime, (int) $block->getChangedTime());
+    $this->assertGreaterThanOrEqual($requestTime, (int) $block->getChangedTime());
     $this->assertLessThanOrEqual(time(), $block->getChangedTime());
     $this->assertSame('en', $block->language()->getId());
     $this->assertSame('<h3>My second content block body</h3>', $block->body->value);
diff --git a/core/modules/block_content/tests/src/Kernel/Migrate/d6/MigrateCustomBlockContentTranslationTest.php b/core/modules/block_content/tests/src/Kernel/Migrate/d6/MigrateCustomBlockContentTranslationTest.php
index cc249a9d1e81e4684f6c9be1f65fd09f3928f37e..d8748c7140ca59439b1fa509b9eea70884c33003 100644
--- a/core/modules/block_content/tests/src/Kernel/Migrate/d6/MigrateCustomBlockContentTranslationTest.php
+++ b/core/modules/block_content/tests/src/Kernel/Migrate/d6/MigrateCustomBlockContentTranslationTest.php
@@ -45,7 +45,7 @@ public function testCustomBlockContentTranslation() {
     /** @var \Drupal\block_content\Entity\BlockContent $block */
     $block = BlockContent::load(1)->getTranslation('fr');
     $this->assertSame('fr - Static Block', $block->label());
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $block->getChangedTime());
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $block->getChangedTime());
     $this->assertLessThanOrEqual(time(), $block->getChangedTime());
     $this->assertSame('fr', $block->language()->getId());
     $this->assertSame('<h3>fr - My first content block body</h3>', $block->body->value);
@@ -53,7 +53,7 @@ public function testCustomBlockContentTranslation() {
 
     $block = $block->getTranslation('zu');
     $this->assertSame('My block 1', $block->label());
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $block->getChangedTime());
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $block->getChangedTime());
     $this->assertLessThanOrEqual(time(), $block->getChangedTime());
     $this->assertSame('zu', $block->language()->getId());
     $this->assertSame('<h3>zu - My first content block body</h3>', $block->body->value);
@@ -61,7 +61,7 @@ public function testCustomBlockContentTranslation() {
 
     $block = BlockContent::load(2)->getTranslation('fr');
     $this->assertSame('Encore un bloc statique', $block->label());
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $block->getChangedTime());
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $block->getChangedTime());
     $this->assertLessThanOrEqual(time(), $block->getChangedTime());
     $this->assertSame('fr', $block->language()->getId());
     $this->assertSame('Nom de vocabulaire beaucoup plus long que trente-deux caractères', $block->body->value);
diff --git a/core/modules/comment/tests/src/Kernel/Views/CommentViewsFieldAccessTest.php b/core/modules/comment/tests/src/Kernel/Views/CommentViewsFieldAccessTest.php
index f4fc987dcfb6ae9cdae4b40c70ad2fa5eece47fc..391533cec9c8b38057f9b7cb317e5e2ca14329a8 100644
--- a/core/modules/comment/tests/src/Kernel/Views/CommentViewsFieldAccessTest.php
+++ b/core/modules/comment/tests/src/Kernel/Views/CommentViewsFieldAccessTest.php
@@ -78,7 +78,7 @@ public function testCommentFields() {
     $this->assertFieldAccess('comment', 'homepage', 'https://example.com');
     $this->assertFieldAccess('comment', 'uid', $user->getAccountName());
     // $this->assertFieldAccess('comment', 'created', \Drupal::service('date.formatter')->format(123456));
-    // $this->assertFieldAccess('comment', 'changed', \Drupal::service('date.formatter')->format(REQUEST_TIME));
+    // $this->assertFieldAccess('comment', 'changed', \Drupal::service('date.formatter')->format(\Drupal::time()->getRequestTime()));
     $this->assertFieldAccess('comment', 'status', 'On');
   }
 
diff --git a/core/modules/datetime/tests/src/Kernel/Views/FilterDateTimeTest.php b/core/modules/datetime/tests/src/Kernel/Views/FilterDateTimeTest.php
index d1dc01e6c20afe7497dd1b11da5527ad3bad6e89..96d47dc432125a6ff202d737078e7a394c09acd5 100644
--- a/core/modules/datetime/tests/src/Kernel/Views/FilterDateTimeTest.php
+++ b/core/modules/datetime/tests/src/Kernel/Views/FilterDateTimeTest.php
@@ -38,7 +38,7 @@ class FilterDateTimeTest extends DateTimeHandlerTestBase {
   protected function setUp($import_test_views = TRUE): void {
     parent::setUp($import_test_views);
 
-    static::$date = REQUEST_TIME + 86400;
+    static::$date = \Drupal::time()->getRequestTime() + 86400;
 
     // Set the timezone.
     date_default_timezone_set(static::$timezone);
diff --git a/core/modules/field/tests/src/Kernel/Timestamp/TimestampFormatterTest.php b/core/modules/field/tests/src/Kernel/Timestamp/TimestampFormatterTest.php
index 709115c6e61b68060e3a9be8e50cd9c66a46ff96..5fa292746ad599f31e3f04f47e490d3cc5a2d5f0 100644
--- a/core/modules/field/tests/src/Kernel/Timestamp/TimestampFormatterTest.php
+++ b/core/modules/field/tests/src/Kernel/Timestamp/TimestampFormatterTest.php
@@ -124,7 +124,7 @@ public function testTimestampFormatter() {
         $timezone = NULL;
       }
 
-      $value = REQUEST_TIME - 87654321;
+      $value = \Drupal::time()->getRequestTime() - 87654321;
       $expected = \Drupal::service('date.formatter')->format($value, $date_format, $custom_date_format, $timezone);
 
       $component = $this->display->getComponent($this->fieldName);
diff --git a/core/modules/file/tests/src/Kernel/DeleteTest.php b/core/modules/file/tests/src/Kernel/DeleteTest.php
index e3ca3f5e3c0a3c8d77162bd5c658a240ba17ea22..fb7345aeac770bc7020e313411512bcc4eea4fd5 100644
--- a/core/modules/file/tests/src/Kernel/DeleteTest.php
+++ b/core/modules/file/tests/src/Kernel/DeleteTest.php
@@ -65,7 +65,7 @@ public function testInUse() {
     // would set the timestamp.
     Database::getConnection()->update('file_managed')
       ->fields([
-        'changed' => REQUEST_TIME - ($this->config('system.file')->get('temporary_maximum_age') + 1),
+        'changed' => \Drupal::time()->getRequestTime() - ($this->config('system.file')->get('temporary_maximum_age') + 3),
       ])
       ->condition('fid', $file->id())
       ->execute();
@@ -92,7 +92,7 @@ public function testCronDeleteNonExistingTemporary() {
     // configuration value.
     \Drupal::database()->update('file_managed')
       ->fields([
-        'changed' => REQUEST_TIME - ($this->config('system.file')->get('temporary_maximum_age') + 1),
+        'changed' => \Drupal::time()->getRequestTime() - ($this->config('system.file')->get('temporary_maximum_age') + 3),
       ])
       ->condition('fid', $file->id())
       ->execute();
diff --git a/core/modules/file/tests/src/Kernel/UsageTest.php b/core/modules/file/tests/src/Kernel/UsageTest.php
index 1430b700260337584834e2248991acc2f61c3560..374eff614ec31d192b70d42eb56a49755ff22732 100644
--- a/core/modules/file/tests/src/Kernel/UsageTest.php
+++ b/core/modules/file/tests/src/Kernel/UsageTest.php
@@ -163,7 +163,7 @@ public function createTempFiles() {
     $connection->update('file_managed')
       ->fields([
         'status' => 0,
-        'changed' => REQUEST_TIME - $this->config('system.file')->get('temporary_maximum_age') - 1,
+        'changed' => \Drupal::time()->getRequestTime() - $this->config('system.file')->get('temporary_maximum_age') - 1,
       ])
       ->condition('fid', $temp_old->id())
       ->execute();
@@ -180,7 +180,7 @@ public function createTempFiles() {
     // Permanent file that is old.
     $perm_old = $fileRepository->writeData('', $destination);
     $connection->update('file_managed')
-      ->fields(['changed' => REQUEST_TIME - $this->config('system.file')->get('temporary_maximum_age') - 1])
+      ->fields(['changed' => \Drupal::time()->getRequestTime() - $this->config('system.file')->get('temporary_maximum_age') - 1])
       ->condition('fid', $temp_old->id())
       ->execute();
     $this->assertFileExists($perm_old->getFileUri());
diff --git a/core/modules/file/tests/src/Kernel/Views/FileViewsFieldAccessTest.php b/core/modules/file/tests/src/Kernel/Views/FileViewsFieldAccessTest.php
index 902ee67e4ee234876bfca7555689454c906e8652..43a904c7e90b900f2b1ef6354bd722b2bab32aee 100644
--- a/core/modules/file/tests/src/Kernel/Views/FileViewsFieldAccessTest.php
+++ b/core/modules/file/tests/src/Kernel/Views/FileViewsFieldAccessTest.php
@@ -64,7 +64,7 @@ public function testFileFields() {
     $this->assertFieldAccess('file', 'filesize', '4 bytes');
     $this->assertFieldAccess('file', 'status', 'Permanent');
     // $this->assertFieldAccess('file', 'created', \Drupal::service('date.formatter')->format(123456));
-    // $this->assertFieldAccess('file', 'changed', \Drupal::service('date.formatter')->format(REQUEST_TIME));
+    // $this->assertFieldAccess('file', 'changed', \Drupal::service('date.formatter')->format(\Drupal::time()->getRequestTime()));
   }
 
 }
diff --git a/core/modules/history/tests/src/Kernel/Views/HistoryTimestampTest.php b/core/modules/history/tests/src/Kernel/Views/HistoryTimestampTest.php
index 30c8a8035135b82043afb314ee60fd937498fca0..50c2931c1be53a8ffe11ca74f9c8c17ea4ee1feb 100644
--- a/core/modules/history/tests/src/Kernel/Views/HistoryTimestampTest.php
+++ b/core/modules/history/tests/src/Kernel/Views/HistoryTimestampTest.php
@@ -69,18 +69,19 @@ public function testHandlers() {
     \Drupal::currentUser()->setAccount($account);
 
     $connection = Database::getConnection();
+    $requestTime = \Drupal::time()->getRequestTime();
     $connection->insert('history')
       ->fields([
         'uid' => $account->id(),
         'nid' => $nodes[0]->id(),
-        'timestamp' => REQUEST_TIME - 100,
+        'timestamp' => $requestTime - 100,
       ])->execute();
 
     $connection->insert('history')
       ->fields([
         'uid' => $account->id(),
         'nid' => $nodes[1]->id(),
-        'timestamp' => REQUEST_TIME + 100,
+        'timestamp' => $requestTime + 100,
       ])->execute();
 
     $column_map = [
diff --git a/core/modules/menu_link_content/tests/src/Kernel/MenuLinksTest.php b/core/modules/menu_link_content/tests/src/Kernel/MenuLinksTest.php
index 528c2bbf62cc14cbf18bfee5ddd1dc50a0d34b78..ff9cc7f33691a4809989efe0c8f451358585f37b 100644
--- a/core/modules/menu_link_content/tests/src/Kernel/MenuLinksTest.php
+++ b/core/modules/menu_link_content/tests/src/Kernel/MenuLinksTest.php
@@ -146,7 +146,7 @@ public function testCreateLink() {
     $link = MenuLinkContent::create($options);
     $link->save();
     // Make sure the changed timestamp is set.
-    $this->assertEquals(REQUEST_TIME, $link->getChangedTime(), 'Creating a menu link sets the "changed" timestamp.');
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $link->getChangedTime(), 'Creating a menu link sets the "changed" timestamp.');
     $options = [
       'title' => 'Test Link',
     ];
@@ -154,7 +154,7 @@ public function testCreateLink() {
     $link->changed->value = 0;
     $link->save();
     // Make sure the changed timestamp is updated.
-    $this->assertEquals(REQUEST_TIME, $link->getChangedTime(), 'Changing a menu link sets "changed" timestamp.');
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $link->getChangedTime(), 'Changing a menu link sets "changed" timestamp.');
   }
 
   /**
diff --git a/core/modules/node/tests/src/Kernel/Views/NodeViewsFieldAccessTest.php b/core/modules/node/tests/src/Kernel/Views/NodeViewsFieldAccessTest.php
index 0a6a56cf96b63eee469d3bc1fa88c126ad516244..a4b6a0e2b988e0962728863e2e7a11c518ec64b4 100644
--- a/core/modules/node/tests/src/Kernel/Views/NodeViewsFieldAccessTest.php
+++ b/core/modules/node/tests/src/Kernel/Views/NodeViewsFieldAccessTest.php
@@ -68,7 +68,7 @@ public function testNodeFields() {
     $this->assertFieldAccess('node', 'sticky', 'Off');
 
     // $this->assertFieldAccess('node', 'created', \Drupal::service('date.formatter')->format(123456));
-    // $this->assertFieldAccess('node', 'changed', \Drupal::service('date.formatter')->format(REQUEST_TIME));
+    // $this->assertFieldAccess('node', 'changed', \Drupal::service('date.formatter')->format(\Drupal::time()->getRequestTime()));
   }
 
 }
diff --git a/core/modules/system/tests/modules/entity_test/src/Plugin/Field/FieldType/ChangedTestItem.php b/core/modules/system/tests/modules/entity_test/src/Plugin/Field/FieldType/ChangedTestItem.php
index 0e0a46c16bb23f1b46607b719f033df0cf7c69e8..66b5b57f487e0d250be1a15a36c5adb4c46d7ef6 100644
--- a/core/modules/system/tests/modules/entity_test/src/Plugin/Field/FieldType/ChangedTestItem.php
+++ b/core/modules/system/tests/modules/entity_test/src/Plugin/Field/FieldType/ChangedTestItem.php
@@ -27,7 +27,7 @@ class ChangedTestItem extends ChangedItem {
   public function preSave() {
     parent::preSave();
 
-    if ($this->value == REQUEST_TIME) {
+    if ($this->value == \Drupal::time()->getRequestTime()) {
       // During a test the request time is immutable. To allow tests of the
       // algorithm of
       // Drupal\Core\Field\Plugin\Field\FieldType\ChangedItem::preSave() we need
diff --git a/core/modules/system/tests/src/Kernel/System/CronQueueTest.php b/core/modules/system/tests/src/Kernel/System/CronQueueTest.php
index e450e3a3837ef58630ae7f7c89d3b7e0a9134fbe..95567ee2c66eb179976644d3be8512b0e27d38ea 100644
--- a/core/modules/system/tests/src/Kernel/System/CronQueueTest.php
+++ b/core/modules/system/tests/src/Kernel/System/CronQueueTest.php
@@ -202,9 +202,10 @@ public function testUncaughtExceptions() {
     // The item should be left in the queue.
     $this->assertEquals(1, $queue->numberOfItems(), 'Failing item still in the queue after throwing an exception.');
 
-    // Expire the queue item manually. system_cron() relies in REQUEST_TIME to
-    // find queue items whose expire field needs to be reset to 0. This is a
-    // Kernel test, so REQUEST_TIME won't change when cron runs.
+    // Expire the queue item manually. system_cron() relies in
+    // \Drupal::time()->getRequestTime() to find queue items whose expire field needs to be
+    // reset to 0. This is a Kernel test, so \Drupal::time()->getRequestTime() won't change
+    // when cron runs.
     // @see system_cron()
     // @see \Drupal\Core\Cron::processQueues()
     $this->connection->update('queue')
diff --git a/core/modules/system/tests/src/Kernel/Token/TokenReplaceKernelTest.php b/core/modules/system/tests/src/Kernel/Token/TokenReplaceKernelTest.php
index 802190359b4c89b089f2702d5c9ce0109cc5403c..c17b5793b8a6eed1d5d504b16d003cd1b555a33f 100644
--- a/core/modules/system/tests/src/Kernel/Token/TokenReplaceKernelTest.php
+++ b/core/modules/system/tests/src/Kernel/Token/TokenReplaceKernelTest.php
@@ -156,7 +156,7 @@ public function testSystemSiteTokenReplacement() {
    */
   public function testSystemDateTokenReplacement() {
     // Set time to one hour before request.
-    $date = REQUEST_TIME - 3600;
+    $date = \Drupal::time()->getRequestTime() - 3600;
 
     // Generate and test tokens.
     $tests = [];
diff --git a/core/modules/update/tests/src/Kernel/UpdateDeleteFileIfStaleTest.php b/core/modules/update/tests/src/Kernel/UpdateDeleteFileIfStaleTest.php
index 4b5118c8e9f55d47b4001c9c853965508734c736..16bf30be17680ebf0ee3bc90c8e6568ff163fe0b 100644
--- a/core/modules/update/tests/src/Kernel/UpdateDeleteFileIfStaleTest.php
+++ b/core/modules/update/tests/src/Kernel/UpdateDeleteFileIfStaleTest.php
@@ -31,8 +31,8 @@ public function testUpdateDeleteFileIfStale() {
 
     // During testing, the file change and the stale checking occurs in the same
     // request, so the beginning of request will be before the file changes and
-    // REQUEST_TIME - $filectime is negative or zero. Set the maximum age to a
-    // number greater than that.
+    // \Drupal::time()->getRequestTime() - $filectime is negative or zero.
+    // Set the maximum age to a number even smaller than that.
     $this->config('system.file')
       ->set('temporary_maximum_age', 100000)
       ->save();
diff --git a/core/modules/user/tests/src/Kernel/Views/UserViewsFieldAccessTest.php b/core/modules/user/tests/src/Kernel/Views/UserViewsFieldAccessTest.php
index 3e21632541a3a2c60df32f133197c9d398fae211..e42ce1faba9ed92c9f88bde363f298cb1802fd40 100644
--- a/core/modules/user/tests/src/Kernel/Views/UserViewsFieldAccessTest.php
+++ b/core/modules/user/tests/src/Kernel/Views/UserViewsFieldAccessTest.php
@@ -55,7 +55,7 @@ public function testUserFields() {
     $this->assertFieldAccess('user', 'timezone', 'ut1');
     $this->assertFieldAccess('user', 'status', 'On');
     // $this->assertFieldAccess('user', 'created', \Drupal::service('date.formatter')->format(123456));
-    // $this->assertFieldAccess('user', 'changed', \Drupal::service('date.formatter')->format(REQUEST_TIME));
+    // $this->assertFieldAccess('user', 'changed', \Drupal::service('date.formatter')->format(\Drupal::time()->getRequestTime()));
   }
 
 }
diff --git a/core/modules/user/tests/src/Kernel/WhoIsOnlineBlockTest.php b/core/modules/user/tests/src/Kernel/WhoIsOnlineBlockTest.php
index ec84fcfacfbf136d00a242fb421cfc198aa29a77..4582e3455d0be3d3a009d36aedf133598fcafd14 100644
--- a/core/modules/user/tests/src/Kernel/WhoIsOnlineBlockTest.php
+++ b/core/modules/user/tests/src/Kernel/WhoIsOnlineBlockTest.php
@@ -72,7 +72,6 @@ protected function setUp(): void {
    * Tests the Who's Online block.
    */
   public function testWhoIsOnlineBlock() {
-    $request_time = \Drupal::time()->getRequestTime();
     // Generate users.
     $user1 = User::create([
       'name' => 'user1',
@@ -80,7 +79,8 @@ public function testWhoIsOnlineBlock() {
     ]);
     $user1->addRole('administrator');
     $user1->activate();
-    $user1->setLastAccessTime($request_time);
+    $requestTime = \Drupal::time()->getRequestTime();
+    $user1->setLastAccessTime($requestTime);
     $user1->save();
 
     $user2 = User::create([
@@ -88,7 +88,7 @@ public function testWhoIsOnlineBlock() {
       'mail' => 'user2@example.com',
     ]);
     $user2->activate();
-    $user2->setLastAccessTime($request_time + 1);
+    $user2->setLastAccessTime($requestTime + 1);
     $user2->save();
 
     $user3 = User::create([
@@ -97,7 +97,7 @@ public function testWhoIsOnlineBlock() {
     ]);
     $user3->activate();
     // Insert an inactive user who should not be seen in the block.
-    $inactive_time = $request_time - (60 * 60);
+    $inactive_time = $requestTime - (60 * 60);
     $user3->setLastAccessTime($inactive_time);
     $user3->save();
 
diff --git a/core/modules/views/tests/src/Kernel/Handler/FieldDropbuttonTest.php b/core/modules/views/tests/src/Kernel/Handler/FieldDropbuttonTest.php
index d3dafb9bd5766a4631dfd96165a32e8f0b5ad9c8..46c91f7720763985b8dffae68295502661b06414 100644
--- a/core/modules/views/tests/src/Kernel/Handler/FieldDropbuttonTest.php
+++ b/core/modules/views/tests/src/Kernel/Handler/FieldDropbuttonTest.php
@@ -87,26 +87,27 @@ protected function setUp($import_test_views = TRUE): void {
     $admin = $this->createUser();
 
     // And three nodes.
+    $requestTime = \Drupal::time()->getRequestTime();
     $this->node1 = $this->createNode([
       'type' => 'bar',
       'title' => 'foo',
       'status' => 1,
       'uid' => $admin->id(),
-      'created' => REQUEST_TIME - 10,
+      'created' => $requestTime - 10,
     ]);
     $this->node2 = $this->createNode([
       'type' => 'foo',
       'title' => 'foo',
       'status' => 1,
       'uid' => $admin->id(),
-      'created' => REQUEST_TIME - 5,
+      'created' => $requestTime - 5,
     ]);
     $this->node3 = $this->createNode([
       'type' => 'bar',
       'title' => 'bars',
       'status' => 1,
       'uid' => $admin->id(),
-      'created' => REQUEST_TIME,
+      'created' => $requestTime,
     ]);
 
     // Now create a user with the ability to edit bar but not foo.
diff --git a/core/modules/views/tests/src/Kernel/Handler/FieldFieldTest.php b/core/modules/views/tests/src/Kernel/Handler/FieldFieldTest.php
index 995b9af0b3d20468db82c5b93b8aa29490643c32..2d33f07cd1c70db4d4c00baabae1a4d0421878ba 100644
--- a/core/modules/views/tests/src/Kernel/Handler/FieldFieldTest.php
+++ b/core/modules/views/tests/src/Kernel/Handler/FieldFieldTest.php
@@ -89,7 +89,7 @@ protected function setUp($import_test_views = TRUE): void {
       $this->testUsers[$i] = User::create([
         'name' => 'test ' . $i,
         'timezone' => User::getAllowedTimezones()[$i],
-        'created' => REQUEST_TIME - rand(0, 3600),
+        'created' => \Drupal::time()->getRequestTime() - rand(0, 3600),
       ]);
       $this->testUsers[$i]->save();
     }
diff --git a/core/modules/views/tests/src/Kernel/Plugin/CacheTest.php b/core/modules/views/tests/src/Kernel/Plugin/CacheTest.php
index fd0812c7bab0deb44dfab9a362b5072eec96bfaa..91a4f425024698d6642ff54d05b78e83483e42c4 100644
--- a/core/modules/views/tests/src/Kernel/Plugin/CacheTest.php
+++ b/core/modules/views/tests/src/Kernel/Plugin/CacheTest.php
@@ -43,7 +43,7 @@ protected function setUp($import_test_views = TRUE): void {
     $this->installEntitySchema('user');
 
     // Setup the current time properly.
-    \Drupal::request()->server->set('REQUEST_TIME', time());
+    \Drupal::request()->server->set('REQUEST_TIME', \Drupal::time()->getCurrentTime());
   }
 
   /**
diff --git a/core/phpstan-baseline.neon b/core/phpstan-baseline.neon
index e727def905d1586b8f80c3f2134a3c6528bff851..31ae8c3284bf4b5703bedd6d30acc873afd89abb 100644
--- a/core/phpstan-baseline.neon
+++ b/core/phpstan-baseline.neon
@@ -993,16 +993,6 @@ parameters:
 			count: 1
 			path: modules/block_content/tests/src/Functional/BlockContentSaveTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 2
-			path: modules/block_content/tests/src/Kernel/Migrate/d6/MigrateBlockContentTest.php
-
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 3
-			path: modules/block_content/tests/src/Kernel/Migrate/d6/MigrateCustomBlockContentTranslationTest.php
-
 		-
 			message: "#^Variable \\$callable in empty\\(\\) always exists and is not falsy\\.$#"
 			count: 1
@@ -1183,11 +1173,6 @@ parameters:
 			count: 4
 			path: modules/datetime/tests/src/Functional/DateTimeFieldTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 1
-			path: modules/datetime/tests/src/Kernel/Views/FilterDateTimeTest.php
-
 		-
 			message: "#^Method Drupal\\\\datetime_range\\\\Plugin\\\\Field\\\\FieldType\\\\DateRangeFieldItemList\\:\\:defaultValuesForm\\(\\) should return array but return statement is missing\\.$#"
 			count: 1
@@ -1243,11 +1228,6 @@ parameters:
 			count: 1
 			path: modules/field/tests/src/Kernel/FieldAttachStorageTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 1
-			path: modules/field/tests/src/Kernel/Timestamp/TimestampFormatterTest.php
-
 		-
 			message: "#^Variable \\$entity_display might not be defined\\.$#"
 			count: 1
@@ -1338,21 +1318,11 @@ parameters:
 			count: 1
 			path: modules/file/tests/src/Functional/FileUploadJsonCookieTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 2
-			path: modules/file/tests/src/Kernel/DeleteTest.php
-
 		-
 			message: "#^Variable \\$unexpected in empty\\(\\) always exists and is not falsy\\.$#"
 			count: 1
 			path: modules/file/tests/src/Kernel/FileManagedUnitTestBase.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 2
-			path: modules/file/tests/src/Kernel/UsageTest.php
-
 		-
 			message: "#^Variable \\$rows might not be defined\\.$#"
 			count: 1
@@ -1378,11 +1348,6 @@ parameters:
 			count: 1
 			path: modules/history/src/Plugin/views/filter/HistoryUserTimestamp.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 2
-			path: modules/history/tests/src/Kernel/Views/HistoryTimestampTest.php
-
 		-
 			message: "#^Variable \\$image_style in empty\\(\\) always exists and is not falsy\\.$#"
 			count: 1
@@ -1601,11 +1566,6 @@ parameters:
 			count: 1
 			path: modules/menu_link_content/src/Plugin/Menu/MenuLinkContent.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 2
-			path: modules/menu_link_content/tests/src/Kernel/MenuLinksTest.php
-
 		-
 			message: "#^Method Drupal\\\\menu_ui\\\\MenuForm\\:\\:save\\(\\) should return int but return statement is missing\\.$#"
 			count: 1
@@ -2096,11 +2056,6 @@ parameters:
 			count: 1
 			path: modules/system/tests/modules/deprecation_test/src/DeprecatedController.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 1
-			path: modules/system/tests/modules/entity_test/src/Plugin/Field/FieldType/ChangedTestItem.php
-
 		-
 			message: "#^Variable \\$options might not be defined\\.$#"
 			count: 1
@@ -2177,11 +2132,6 @@ parameters:
 			count: 2
 			path: modules/system/tests/src/Functional/Theme/ThemeUiTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 1
-			path: modules/system/tests/src/Kernel/Token/TokenReplaceKernelTest.php
-
 		-
 			message: "#^Variable \\$help_message might not be defined\\.$#"
 			count: 1
@@ -2653,16 +2603,6 @@ parameters:
 			count: 2
 			path: modules/views/tests/src/FunctionalJavascript/ClickSortingAJAXTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 3
-			path: modules/views/tests/src/Kernel/Handler/FieldDropbuttonTest.php
-
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 1
-			path: modules/views/tests/src/Kernel/Handler/FieldFieldTest.php
-
 		-
 			message: "#^Variable \\$rand1 might not be defined\\.$#"
 			count: 2
@@ -2849,11 +2789,6 @@ parameters:
 			count: 1
 			path: tests/Drupal/KernelTests/Core/Cache/ApcuBackendTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 12
-			path: tests/Drupal/KernelTests/Core/Cache/GenericCacheBackendUnitTestBase.php
-
 		-
 			message: """
 				#^Call to deprecated method expectWarning\\(\\) of class PHPUnit\\\\Framework\\\\TestCase\\:
@@ -2899,21 +2834,11 @@ parameters:
 			count: 3
 			path: tests/Drupal/KernelTests/Core/Database/StatementTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 4
-			path: tests/Drupal/KernelTests/Core/Entity/ContentEntityChangedTest.php
-
 		-
 			message: "#^Variable \\$title might not be defined\\.$#"
 			count: 2
 			path: tests/Drupal/KernelTests/Core/Entity/CreateSampleEntityTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 9
-			path: tests/Drupal/KernelTests/Core/Entity/EntityCrudHookTest.php
-
 		-
 			message: "#^Variable \\$previous_untranslatable_field_value in isset\\(\\) always exists and is not nullable\\.$#"
 			count: 2
@@ -2924,11 +2849,6 @@ parameters:
 			count: 9
 			path: tests/Drupal/KernelTests/Core/Entity/EntitySchemaTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 1
-			path: tests/Drupal/KernelTests/Core/Entity/EntityTypeConstraintsTest.php
-
 		-
 			message: "#^Variable \\$e might not be defined\\.$#"
 			count: 1
@@ -2954,11 +2874,6 @@ parameters:
 			count: 1
 			path: tests/Drupal/KernelTests/Core/Image/ToolkitGdTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 1
-			path: tests/Drupal/KernelTests/Core/KeyValueStore/GarbageCollectionTest.php
-
 		-
 			message: """
 				#^Call to deprecated method expectErrorMessage\\(\\) of class PHPUnit\\\\Framework\\\\TestCase\\:
@@ -2967,16 +2882,6 @@ parameters:
 			count: 1
 			path: tests/Drupal/KernelTests/Core/Render/Element/MachineNameTest.php
 
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 1
-			path: tests/Drupal/KernelTests/Core/TempStore/TempStoreDatabaseTest.php
-
-		-
-			message: "#^Call to deprecated constant REQUEST_TIME\\: Deprecated in drupal\\:8\\.3\\.0 and is removed from drupal\\:11\\.0\\.0\\. Use \\\\Drupal\\:\\:time\\(\\)\\-\\>getRequestTime\\(\\); $#"
-			count: 5
-			path: tests/Drupal/KernelTests/Core/TypedData/TypedDataTest.php
-
 		-
 			message: "#^Variable \\$value in isset\\(\\) always exists and is not nullable\\.$#"
 			count: 1
diff --git a/core/tests/Drupal/KernelTests/Core/Cache/GenericCacheBackendUnitTestBase.php b/core/tests/Drupal/KernelTests/Core/Cache/GenericCacheBackendUnitTestBase.php
index 0655ba469b7dd61dffd70c80a0a6f20ca82dccc5..e17476c02e015d1fd1c302406e33d57277591060 100644
--- a/core/tests/Drupal/KernelTests/Core/Cache/GenericCacheBackendUnitTestBase.php
+++ b/core/tests/Drupal/KernelTests/Core/Cache/GenericCacheBackendUnitTestBase.php
@@ -144,28 +144,28 @@ public function testSetGet() {
     $this->assertSame($with_backslash, $cached->data);
     $this->assertTrue($cached->valid, 'Item is marked as valid.');
     // We need to round because microtime may be rounded up in the backend.
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $cached->created);
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $cached->created);
     $this->assertLessThanOrEqual(round(microtime(TRUE), 3), $cached->created);
     $this->assertEquals(Cache::PERMANENT, $cached->expire, 'Expire time is correct.');
 
     $this->assertFalse($backend->get('test2'), "Backend does not contain data for cache id test2.");
-    $backend->set('test2', ['value' => 3], REQUEST_TIME + 3);
+    $backend->set('test2', ['value' => 3], \Drupal::time()->getRequestTime() + 3);
     $cached = $backend->get('test2');
     $this->assertIsObject($cached);
     $this->assertSame(['value' => 3], $cached->data);
     $this->assertTrue($cached->valid, 'Item is marked as valid.');
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $cached->created);
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $cached->created);
     $this->assertLessThanOrEqual(round(microtime(TRUE), 3), $cached->created);
-    $this->assertEquals(REQUEST_TIME + 3, $cached->expire, 'Expire time is correct.');
+    $this->assertEquals(\Drupal::time()->getRequestTime() + 3, $cached->expire, 'Expire time is correct.');
 
-    $backend->set('test3', 'foobar', REQUEST_TIME - 3);
+    $backend->set('test3', 'foobar', \Drupal::time()->getRequestTime() - 3);
     $this->assertFalse($backend->get('test3'), 'Invalid item not returned.');
     $cached = $backend->get('test3', TRUE);
     $this->assertIsObject($cached);
     $this->assertFalse($cached->valid, 'Item is marked as valid.');
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $cached->created);
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $cached->created);
     $this->assertLessThanOrEqual(round(microtime(TRUE), 3), $cached->created);
-    $this->assertEquals(REQUEST_TIME - 3, $cached->expire, 'Expire time is correct.');
+    $this->assertEquals(\Drupal::time()->getRequestTime() - 3, $cached->expire, 'Expire time is correct.');
 
     $this->assertFalse($backend->get('test4'), "Backend does not contain data for cache id test4.");
     $with_eof = ['foo' => "\nEOF\ndata"];
@@ -174,7 +174,7 @@ public function testSetGet() {
     $this->assertIsObject($cached);
     $this->assertSame($with_eof, $cached->data);
     $this->assertTrue($cached->valid, 'Item is marked as valid.');
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $cached->created);
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $cached->created);
     $this->assertLessThanOrEqual(round(microtime(TRUE), 3), $cached->created);
     $this->assertEquals(Cache::PERMANENT, $cached->expire, 'Expire time is correct.');
 
@@ -185,7 +185,7 @@ public function testSetGet() {
     $this->assertIsObject($cached);
     $this->assertSame($with_eof_and_semicolon, $cached->data);
     $this->assertTrue($cached->valid, 'Item is marked as valid.');
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $cached->created);
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $cached->created);
     $this->assertLessThanOrEqual(round(microtime(TRUE), 3), $cached->created);
     $this->assertEquals(Cache::PERMANENT, $cached->expire, 'Expire time is correct.');
 
@@ -328,7 +328,7 @@ public function testGetMultiple() {
     $this->assertArrayHasKey('test7', $ret, "Existing cache id test7 is set.");
     // Test return - ensure that objects has expected properties.
     $this->assertTrue($ret['test2']->valid, 'Item is marked as valid.');
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $ret['test2']->created);
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $ret['test2']->created);
     $this->assertLessThanOrEqual(round(microtime(TRUE), 3), $ret['test2']->created);
     $this->assertEquals(Cache::PERMANENT, $ret['test2']->expire, 'Expire time is correct.');
     // Test return - ensure it does not contain nonexistent cache ids.
@@ -390,7 +390,7 @@ public function testGetMultiple() {
   public function testSetMultiple() {
     $backend = $this->getCacheBackend();
 
-    $future_expiration = REQUEST_TIME + 100;
+    $future_expiration = \Drupal::time()->getRequestTime() + 100;
 
     // Set multiple testing keys.
     $backend->set('cid_1', 'Some other value');
@@ -407,7 +407,7 @@ public function testSetMultiple() {
 
     $this->assertEquals($items['cid_1']['data'], $cached['cid_1']->data, 'Over-written cache item set correctly.');
     $this->assertTrue($cached['cid_1']->valid, 'Item is marked as valid.');
-    $this->assertGreaterThanOrEqual(REQUEST_TIME, $cached['cid_1']->created);
+    $this->assertGreaterThanOrEqual(\Drupal::time()->getRequestTime(), $cached['cid_1']->created);
     $this->assertLessThanOrEqual(round(microtime(TRUE), 3), $cached['cid_1']->created);
     $this->assertEquals(CacheBackendInterface::CACHE_PERMANENT, $cached['cid_1']->expire, 'Cache expiration defaults to permanent.');
 
diff --git a/core/tests/Drupal/KernelTests/Core/Entity/ContentEntityChangedTest.php b/core/tests/Drupal/KernelTests/Core/Entity/ContentEntityChangedTest.php
index c60c16413c6177771afe02be895b046fd0d5c7e7..017fc90aea8237c0b0b8ce9160cc25639df35b28 100644
--- a/core/tests/Drupal/KernelTests/Core/Entity/ContentEntityChangedTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Entity/ContentEntityChangedTest.php
@@ -75,10 +75,8 @@ public function testChanged() {
     ]);
     $entity->save();
 
-    $this->assertTrue(
-      $entity->getChangedTime() >= REQUEST_TIME,
-      'Changed time of original language is valid.'
-    );
+    $requestTime = \Drupal::time()->getRequestTime();
+    $this->assertGreaterThanOrEqual($requestTime, $entity->getChangedTime(), 'Changed time of original language is valid.');
 
     // We can't assert equality here because the created time is set to the
     // request time, while instances of ChangedTestItem use the current
@@ -86,7 +84,7 @@ public function testChanged() {
     // between the created time and now.
     $this->assertTrue(
       ($entity->getChangedTime() >= $entity->get('created')->value) &&
-      (($entity->getChangedTime() - $entity->get('created')->value) <= time() - REQUEST_TIME),
+      (($entity->getChangedTime() - $entity->get('created')->value) <= time() - $requestTime),
       'Changed and created time of original language can be assumed to be identical.'
     );
 
@@ -254,7 +252,7 @@ public function testRevisionChanged() {
     $entity->save();
 
     $this->assertTrue(
-      $entity->getChangedTime() >= REQUEST_TIME,
+      $entity->getChangedTime() >= \Drupal::time()->getRequestTime(),
       'Changed time of original language is valid.'
     );
 
@@ -263,7 +261,7 @@ public function testRevisionChanged() {
     // timestamp every time.
     $this->assertTrue(
       ($entity->getChangedTime() >= $entity->get('created')->value) &&
-      (($entity->getChangedTime() - $entity->get('created')->value) <= time() - REQUEST_TIME),
+      (($entity->getChangedTime() - $entity->get('created')->value) <= time() - \Drupal::time()->getRequestTime()),
       'Changed and created time of original language can be assumed to be identical.'
     );
 
diff --git a/core/tests/Drupal/KernelTests/Core/Entity/EntityCrudHookTest.php b/core/tests/Drupal/KernelTests/Core/Entity/EntityCrudHookTest.php
index 414d11b4ef4df92bf4b859df169658a9a394e0bb..95e380d1b20912ecb96abce3c220d00423de1f77 100644
--- a/core/tests/Drupal/KernelTests/Core/Entity/EntityCrudHookTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Entity/EntityCrudHookTest.php
@@ -168,8 +168,8 @@ public function testCommentHooks() {
       'promote' => 0,
       'sticky' => 0,
       'langcode' => LanguageInterface::LANGCODE_NOT_SPECIFIED,
-      'created' => REQUEST_TIME,
-      'changed' => REQUEST_TIME,
+      'created' => \Drupal::time()->getRequestTime(),
+      'changed' => \Drupal::time()->getRequestTime(),
     ]);
     $node->save();
     $nid = $node->id();
@@ -183,8 +183,8 @@ public function testCommentHooks() {
       'field_name' => 'comment',
       'uid' => $account->id(),
       'subject' => 'Test comment',
-      'created' => REQUEST_TIME,
-      'changed' => REQUEST_TIME,
+      'created' => \Drupal::time()->getRequestTime(),
+      'changed' => \Drupal::time()->getRequestTime(),
       'status' => 1,
       'langcode' => LanguageInterface::LANGCODE_NOT_SPECIFIED,
     ]);
@@ -250,8 +250,8 @@ public function testFileHooks() {
       'filemime' => 'text/plain',
       'filesize' => filesize($url),
       'status' => 1,
-      'created' => REQUEST_TIME,
-      'changed' => REQUEST_TIME,
+      'created' => \Drupal::time()->getRequestTime(),
+      'changed' => \Drupal::time()->getRequestTime(),
     ]);
 
     $this->assertHookMessageOrder([
@@ -313,8 +313,8 @@ public function testNodeHooks() {
       'promote' => 0,
       'sticky' => 0,
       'langcode' => LanguageInterface::LANGCODE_NOT_SPECIFIED,
-      'created' => REQUEST_TIME,
-      'changed' => REQUEST_TIME,
+      'created' => \Drupal::time()->getRequestTime(),
+      'changed' => \Drupal::time()->getRequestTime(),
     ]);
 
     $this->assertHookMessageOrder([
@@ -498,7 +498,7 @@ public function testUserHooks() {
     $account = User::create([
       'name' => 'Test user',
       'mail' => 'test@example.com',
-      'created' => REQUEST_TIME,
+      'created' => \Drupal::time()->getRequestTime(),
       'status' => 1,
       'language' => 'en',
     ]);
diff --git a/core/tests/Drupal/KernelTests/Core/Entity/EntityTypeConstraintsTest.php b/core/tests/Drupal/KernelTests/Core/Entity/EntityTypeConstraintsTest.php
index 1d0aa063fae41864c4af1ff9cf25a59ac1dcba6c..529d0f623f7e7ea666c9d95aa98694b8f60900be 100644
--- a/core/tests/Drupal/KernelTests/Core/Entity/EntityTypeConstraintsTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Entity/EntityTypeConstraintsTest.php
@@ -64,7 +64,7 @@ public function testConstraintValidation() {
     $violations = $entity->validate();
     $this->assertEquals(0, $violations->count(), 'Validation passed.');
     $entity->save();
-    $entity->changed->value = REQUEST_TIME - 86400;
+    $entity->changed->value = \Drupal::time()->getRequestTime() - 86400;
     $violations = $entity->validate();
     $this->assertEquals(1, $violations->count(), 'Validation failed.');
     $this->assertEquals('The content has either been modified by another user, or you have already submitted modifications. As a result, your changes cannot be saved.', $violations[0]->getMessage());
diff --git a/core/tests/Drupal/KernelTests/Core/KeyValueStore/GarbageCollectionTest.php b/core/tests/Drupal/KernelTests/Core/KeyValueStore/GarbageCollectionTest.php
index 669a835b086b0267d050991a96e5bff6eb143467..904eeab89e7df381923ad60e960bc0d3650061b3 100644
--- a/core/tests/Drupal/KernelTests/Core/KeyValueStore/GarbageCollectionTest.php
+++ b/core/tests/Drupal/KernelTests/Core/KeyValueStore/GarbageCollectionTest.php
@@ -43,7 +43,7 @@ public function testGarbageCollection() {
           'collection' => $collection,
         ])
         ->fields([
-          'expire' => REQUEST_TIME - 1,
+          'expire' => \Drupal::time()->getRequestTime() - 1,
         ])
         ->execute();
     }
diff --git a/core/tests/Drupal/KernelTests/Core/TempStore/TempStoreDatabaseTest.php b/core/tests/Drupal/KernelTests/Core/TempStore/TempStoreDatabaseTest.php
index 20acd1083b6c90250ce7ff6996f090f9d8c88f04..6a0ccb57879efbaa7930963a9fc19ea3c1a2d979 100644
--- a/core/tests/Drupal/KernelTests/Core/TempStore/TempStoreDatabaseTest.php
+++ b/core/tests/Drupal/KernelTests/Core/TempStore/TempStoreDatabaseTest.php
@@ -103,7 +103,7 @@ public function testSharedTempStore() {
     // Now manually expire the item (this is not exposed by the API) and then
     // assert it is no longer accessible.
     $database->update('key_value_expire')
-      ->fields(['expire' => REQUEST_TIME - 1])
+      ->fields(['expire' => \Drupal::time()->getRequestTime() - 1])
       ->condition('collection', "tempstore.shared.$collection")
       ->condition('name', $key)
       ->execute();
diff --git a/core/tests/Drupal/KernelTests/Core/TypedData/TypedDataTest.php b/core/tests/Drupal/KernelTests/Core/TypedData/TypedDataTest.php
index 87d4b1a47493e90f84c5c18697fdf2eec696bc82..0d21bb88539318efafe517f4f87434cca9934809 100644
--- a/core/tests/Drupal/KernelTests/Core/TypedData/TypedDataTest.php
+++ b/core/tests/Drupal/KernelTests/Core/TypedData/TypedDataTest.php
@@ -226,12 +226,13 @@ public function testGetAndSet() {
     $this->assertNull($typed_data->getDateTime());
 
     // Timestamp type.
-    $value = REQUEST_TIME;
+    $requestTime = \Drupal::time()->getRequestTime();
+    $value = $requestTime;
     $typed_data = $this->createTypedData(['type' => 'timestamp'], $value);
     $this->assertInstanceOf(DateTimeInterface::class, $typed_data);
     $this->assertSame($typed_data->getValue(), $value, 'Timestamp value was fetched.');
     $this->assertEquals(0, $typed_data->validate()->count());
-    $new_value = REQUEST_TIME + 1;
+    $new_value = $requestTime + 1;
     $typed_data->setValue($new_value);
     $this->assertSame($typed_data->getValue(), $new_value, 'Timestamp value was changed and set.');
     $this->assertEquals(0, $typed_data->validate()->count());
@@ -241,10 +242,10 @@ public function testGetAndSet() {
     $typed_data->setValue('invalid');
     $this->assertEquals(1, $typed_data->validate()->count(), 'Validation detected invalid value.');
     // Check implementation of DateTimeInterface.
-    $typed_data = $this->createTypedData(['type' => 'timestamp'], REQUEST_TIME);
+    $typed_data = $this->createTypedData(['type' => 'timestamp'], $requestTime);
     $this->assertInstanceOf(DrupalDateTime::class, $typed_data->getDateTime());
-    $typed_data->setDateTime(DrupalDateTime::createFromTimestamp(REQUEST_TIME + 1));
-    $this->assertEquals(REQUEST_TIME + 1, $typed_data->getValue());
+    $typed_data->setDateTime(DrupalDateTime::createFromTimestamp($requestTime + 1));
+    $this->assertEquals($requestTime + 1, $typed_data->getValue());
     $typed_data->setValue(NULL);
     $this->assertNull($typed_data->getDateTime());
 
diff --git a/core/tests/Drupal/Tests/Core/Render/RendererTestBase.php b/core/tests/Drupal/Tests/Core/Render/RendererTestBase.php
index 59a66b53bd87f58ce84e3810d8b443a4634ee8dc..8e1b76cc878b0b47a1d7f08c39287873728cc817 100644
--- a/core/tests/Drupal/Tests/Core/Render/RendererTestBase.php
+++ b/core/tests/Drupal/Tests/Core/Render/RendererTestBase.php
@@ -5,6 +5,7 @@
 namespace Drupal\Tests\Core\Render;
 
 use Drupal\Component\Datetime\Time;
+use Drupal\Component\Datetime\TimeInterface;
 use Drupal\Core\Cache\Cache;
 use Drupal\Core\Cache\CacheableMetadata;
 use Drupal\Core\Cache\Context\ContextCacheKeys;
@@ -25,6 +26,13 @@
  */
 abstract class RendererTestBase extends UnitTestCase {
 
+  /**
+   * System time service.
+   *
+   * @var \Drupal\Component\Datetime\TimeInterface
+   */
+  protected TimeInterface $datetimeTime;
+
   /**
    * The tested renderer.
    *
@@ -184,11 +192,13 @@ protected function setUp(): void {
     $this->placeholderGenerator = new PlaceholderGenerator($this->cacheContextsManager, $this->rendererConfig);
     $this->renderCache = new PlaceholderingRenderCache($this->requestStack, $this->cacheFactory, $this->cacheContextsManager, $this->placeholderGenerator);
     $this->renderer = new Renderer($this->callableResolver, $this->themeManager, $this->elementInfo, $this->placeholderGenerator, $this->renderCache, $this->requestStack, $this->rendererConfig);
+    $this->datetimeTime = new Time($this->requestStack);
 
     $container = new ContainerBuilder();
     $container->set('cache_contexts_manager', $this->cacheContextsManager);
     $container->set('render_cache', $this->renderCache);
     $container->set('renderer', $this->renderer);
+    $container->set('datetime.time', $this->datetimeTime);
     \Drupal::setContainer($container);
   }