diff --git a/core/includes/install.core.inc b/core/includes/install.core.inc
index 6c492363da7756bec0dc45d459f2f88a1f1ff63e..a3e1c9489566e6f173d4d662c9691cde09c440ba 100644
--- a/core/includes/install.core.inc
+++ b/core/includes/install.core.inc
@@ -1209,8 +1209,8 @@ function install_database_errors($database, $settings_file) {
     // Run tasks associated with the database type. Any errors are caught in the
     // calling function.
     Database::addConnectionInfo('default', 'default', $database);
-
-    $errors = db_installer_object($driver, $database['namespace'] ?? NULL)->runTasks();
+    $installer_class = $database['namespace'] . "\\Install\\Tasks";
+    $errors = (new $installer_class())->runTasks();
   }
   return $errors;
 }
diff --git a/core/includes/install.inc b/core/includes/install.inc
index f85499042f8e6045b0e2d1db5ecfde027c9dbe41..2b3232942c332e5d2703b56fec09b9c86b420e97 100644
--- a/core/includes/install.inc
+++ b/core/includes/install.inc
@@ -202,8 +202,7 @@ function drupal_get_database_types() {
         if (file_exists($tasks_file)) {
           $namespace = 'Drupal\\' . $module->getName() . '\\Driver\\Database\\' . $driver_file->filename;
 
-          // The namespace needs to be added for db_installer_object() to find
-          // it.
+          // Add the driver with its own classes' namespace.
           $drivers[$driver_file->filename] = $namespace;
 
           // The directory needs to be added to the autoloader, because this is
@@ -217,7 +216,8 @@ function drupal_get_database_types() {
   }
 
   foreach ($drivers as $driver => $namespace) {
-    $installer = db_installer_object($driver, $namespace);
+    $installer_class = $namespace . "\\Install\\Tasks";
+    $installer = new $installer_class();
     if ($installer->installable()) {
       $databases[$driver] = $installer;
     }
@@ -1167,10 +1167,16 @@ function install_profile_info($profile, $langcode = 'en') {
  * @return \Drupal\Core\Database\Install\Tasks
  *   A class defining the requirements and tasks for installing the database.
  *
+ * @deprecated in drupal:10.0.0 and is removed from drupal:11.0.0. There is no
+ *   replacement.
+ *
+ * @see https://www.drupal.org/node/3256641
  * @see drupal_get_database_types()
  * @see \Drupal\Core\Site\Settings::initialize()
  */
 function db_installer_object($driver, $namespace = NULL) {
+  @trigger_error('db_installer_object() is deprecated in drupal:10.0.0 and is removed from drupal:11.0.0. There is no replacement. See https://www.drupal.org/node/3256641', E_USER_DEPRECATED);
+
   // We cannot use Database::getConnection->getDriverClass() here, because
   // the connection object is not yet functional.
   if ($namespace) {
diff --git a/core/modules/system/tests/src/Kernel/Installer/InstallerDependenciesResolutionTest.php b/core/modules/system/tests/src/Kernel/Installer/InstallerDependenciesResolutionTest.php
index 065ff69bea4c475f4fa89343b19a302bc5e50361..73ec8999f94ca35cab62f5cf5c03d3be8728b9d1 100644
--- a/core/modules/system/tests/src/Kernel/Installer/InstallerDependenciesResolutionTest.php
+++ b/core/modules/system/tests/src/Kernel/Installer/InstallerDependenciesResolutionTest.php
@@ -30,6 +30,9 @@ public function testDependenciesResolution() {
     assert($profile_list instanceof ProfileExtensionList);
     $profile_list->setPathname('testing_missing_dependencies', 'core/profiles/testing_missing_dependencies/testing_missing_dependencies.info.yml');
 
+    // Requires install.inc to be able to use drupal_verify_profile.
+    require_once dirname(__FILE__, 7) . '/includes/install.inc';
+
     $info = drupal_verify_profile([
       'parameters' => ['profile' => 'testing_missing_dependencies'],
       'profile_info' => install_profile_info('testing_missing_dependencies'),
diff --git a/core/tests/Drupal/FunctionalTests/Update/UpdatePathTestBase.php b/core/tests/Drupal/FunctionalTests/Update/UpdatePathTestBase.php
index 22b6aeabc73b551ac55078342a75248ebcf40604..301ac93c3a08196881e3dd32b7793218e43f6877 100644
--- a/core/tests/Drupal/FunctionalTests/Update/UpdatePathTestBase.php
+++ b/core/tests/Drupal/FunctionalTests/Update/UpdatePathTestBase.php
@@ -286,11 +286,9 @@ protected function runDbTasks() {
       ->addArgument(new Reference('language.default'));
     \Drupal::setContainer($container);
 
-    require_once __DIR__ . '/../../../../includes/install.inc';
-    $connection_info = Database::getConnectionInfo();
-    $driver = $connection_info['default']['driver'];
-    $namespace = $connection_info['default']['namespace'] ?? NULL;
-    $errors = db_installer_object($driver, $namespace)->runTasks();
+    // Run database tasks and check for errors.
+    $installer_class = Database::getConnectionInfo()['default']['namespace'] . "\\Install\\Tasks";
+    $errors = (new $installer_class())->runTasks();
     if (!empty($errors)) {
       $this->fail('Failed to run installer database tasks: ' . implode(', ', $errors));
     }
diff --git a/core/tests/Drupal/KernelTests/KernelTestBase.php b/core/tests/Drupal/KernelTests/KernelTestBase.php
index a75d45758cc0347943dc98d3f7a5e69fa71efd0a..148c6d3d941877723c50d0bf0cb4597e4538ccc4 100644
--- a/core/tests/Drupal/KernelTests/KernelTestBase.php
+++ b/core/tests/Drupal/KernelTests/KernelTestBase.php
@@ -378,9 +378,9 @@ private function bootKernel() {
 
     $this->container = $kernel->getContainer();
 
-    // Ensure database tasks have been run.
-    require_once __DIR__ . '/../../../includes/install.inc';
-    $errors = db_installer_object($driver, $namespace)->runTasks();
+    // Run database tasks and check for errors.
+    $installer_class = $namespace . "\\Install\\Tasks";
+    $errors = (new $installer_class())->runTasks();
     if (!empty($errors)) {
       $this->fail('Failed to run installer database tasks: ' . implode(', ', $errors));
     }
diff --git a/core/tests/Drupal/Tests/Core/Database/InstallerObjectTest.php b/core/tests/Drupal/Tests/Core/Database/InstallerObjectTest.php
index 278ace0becd4d233a428a7259e7e54250e8f1c46..80f8a4070599b7bbf4a34026f4a304bf47dc259f 100644
--- a/core/tests/Drupal/Tests/Core/Database/InstallerObjectTest.php
+++ b/core/tests/Drupal/Tests/Core/Database/InstallerObjectTest.php
@@ -21,6 +21,7 @@
  * @preserveGlobalState disabled
  *
  * @group Database
+ * @group legacy
  */
 class InstallerObjectTest extends UnitTestCase {
 
@@ -42,6 +43,7 @@ protected function setUp(): void {
    * @dataProvider providerDbInstallerObject
    */
   public function testDbInstallerObject($driver, $namespace, $expected_class_name) {
+    $this->expectDeprecation('db_installer_object() is deprecated in drupal:10.0.0 and is removed from drupal:11.0.0. There is no replacement. See https://www.drupal.org/node/3256641');
     $object = db_installer_object($driver, $namespace);
     $this->assertEquals(get_class($object), $expected_class_name);
   }