diff --git a/core/tests/Drupal/KernelTests/Core/Theme/MessageTest.php b/core/tests/Drupal/KernelTests/Core/Theme/MessageTest.php
index 5552591ed1..6e594f358e 100644
--- a/core/tests/Drupal/KernelTests/Core/Theme/MessageTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Theme/MessageTest.php
@@ -21,7 +21,7 @@ class MessageTest extends KernelTestBase {
    */
   public function testMessages() {
     // Enable the Classy theme.
-    \Drupal::service('theme_handler')->install(['classy']);
+    \Drupal::service('theme_installer')->install(['classy']);
     $this->config('system.theme')->set('default', 'classy')->save();
 
     \Drupal::messenger()->addError('An error occurred');
diff --git a/core/tests/Drupal/KernelTests/Core/Theme/RegistryTest.php b/core/tests/Drupal/KernelTests/Core/Theme/RegistryTest.php
index 320e92f46a..ffbe543db7 100644
--- a/core/tests/Drupal/KernelTests/Core/Theme/RegistryTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Theme/RegistryTest.php
@@ -67,7 +67,7 @@ public function testRaceCondition() {
    */
   public function testMultipleSubThemes() {
     $theme_handler = \Drupal::service('theme_handler');
-    $theme_handler->install(['test_basetheme', 'test_subtheme', 'test_subsubtheme']);
+    \Drupal::service('theme_installer')->install(['test_basetheme', 'test_subtheme', 'test_subsubtheme']);
 
     $registry_subsub_theme = new Registry($this->root, \Drupal::cache(), \Drupal::lock(), \Drupal::moduleHandler(), $theme_handler, \Drupal::service('theme.initialization'), 'test_subsubtheme');
     $registry_subsub_theme->setThemeManager(\Drupal::theme());
@@ -109,7 +109,7 @@ public function testMultipleSubThemes() {
    */
   public function testSuggestionPreprocessFunctions() {
     $theme_handler = \Drupal::service('theme_handler');
-    $theme_handler->install(['test_theme']);
+    \Drupal::service('theme_installer')->install(['test_theme']);
 
     $registry_theme = new Registry($this->root, \Drupal::cache(), \Drupal::lock(), \Drupal::moduleHandler(), $theme_handler, \Drupal::service('theme.initialization'), 'test_theme');
     $registry_theme->setThemeManager(\Drupal::theme());
@@ -151,7 +151,7 @@ public function testThemeRegistryAlterByTheme() {
 
     /** @var \Drupal\Core\Extension\ThemeHandlerInterface $theme_handler */
     $theme_handler = \Drupal::service('theme_handler');
-    $theme_handler->install(['test_theme']);
+    \Drupal::service('theme_installer')->install(['test_theme']);
     $this->config('system.theme')->set('default', 'test_theme')->save();
 
     $registry = new Registry($this->root, \Drupal::cache(), \Drupal::lock(), \Drupal::moduleHandler(), $theme_handler, \Drupal::service('theme.initialization'), 'test_theme');
@@ -197,7 +197,7 @@ public function testThemeSuggestions() {
    */
   public function testThemeTemplatesRegisteredByModules() {
     $theme_handler = \Drupal::service('theme_handler');
-    $theme_handler->install(['test_theme']);
+    \Drupal::service('theme_installer')->install(['test_theme']);
 
     $registry_theme = new Registry($this->root, \Drupal::cache(), \Drupal::lock(), \Drupal::moduleHandler(), $theme_handler, \Drupal::service('theme.initialization'), 'test_theme');
     $registry_theme->setThemeManager(\Drupal::theme());
diff --git a/core/tests/Drupal/KernelTests/Core/Theme/StableThemeTest.php b/core/tests/Drupal/KernelTests/Core/Theme/StableThemeTest.php
index 8a79a9eff4..50e732631d 100644
--- a/core/tests/Drupal/KernelTests/Core/Theme/StableThemeTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Theme/StableThemeTest.php
@@ -19,11 +19,11 @@ class StableThemeTest extends KernelTestBase {
   public static $modules = ['system'];
 
   /**
-   * The theme handler.
+   * The theme installer.
    *
-   * @var \Drupal\Core\Extension\ThemeHandlerInterface
+   * @var \Drupal\Core\Extension\ThemeInstallerInterface
    */
-  protected $themeHandler;
+  protected $themeInstaller;
 
   /**
    * The theme manager.
@@ -38,7 +38,7 @@ class StableThemeTest extends KernelTestBase {
   protected function setUp() {
     parent::setUp();
 
-    $this->themeHandler = $this->container->get('theme_handler');
+    $this->themeInstaller = $this->container->get('theme_installer');
     $this->themeManager = $this->container->get('theme.manager');
   }
 
@@ -46,7 +46,7 @@ protected function setUp() {
    * Ensures Stable is used by default when no base theme has been defined.
    */
   public function testStableIsDefault() {
-    $this->themeHandler->install(['test_stable']);
+    $this->themeInstaller->install(['test_stable']);
     $this->config('system.theme')->set('default', 'test_stable')->save();
     $theme = $this->themeManager->getActiveTheme();
     /** @var \Drupal\Core\Theme\ActiveTheme $base_theme */
@@ -59,7 +59,7 @@ public function testStableIsDefault() {
    * Tests opting out of Stable by setting the base theme to false.
    */
   public function testWildWest() {
-    $this->themeHandler->install(['test_wild_west']);
+    $this->themeInstaller->install(['test_wild_west']);
     $this->config('system.theme')->set('default', 'test_wild_west')->save();
     $theme = $this->themeManager->getActiveTheme();
     /** @var \Drupal\Core\Theme\ActiveTheme $base_theme */
diff --git a/core/tests/Drupal/KernelTests/Core/Theme/ThemeSettingsTest.php b/core/tests/Drupal/KernelTests/Core/Theme/ThemeSettingsTest.php
index cf0e7d2c21..9e70d19559 100644
--- a/core/tests/Drupal/KernelTests/Core/Theme/ThemeSettingsTest.php
+++ b/core/tests/Drupal/KernelTests/Core/Theme/ThemeSettingsTest.php
@@ -45,7 +45,7 @@ public function testDefaultConfig() {
     $name = 'test_basetheme';
     $path = $this->availableThemes[$name]->getPath();
     $this->assertTrue(file_exists("$path/" . InstallStorage::CONFIG_INSTALL_DIRECTORY . "/$name.settings.yml"));
-    $this->container->get('theme_handler')->install([$name]);
+    $this->container->get('theme_installer')->install([$name]);
     $this->assertIdentical(theme_get_setting('base', $name), 'only');
   }
 
@@ -56,7 +56,7 @@ public function testNoDefaultConfig() {
     $name = 'stark';
     $path = $this->availableThemes[$name]->getPath();
     $this->assertFalse(file_exists("$path/" . InstallStorage::CONFIG_INSTALL_DIRECTORY . "/$name.settings.yml"));
-    $this->container->get('theme_handler')->install([$name]);
+    $this->container->get('theme_installer')->install([$name]);
     $this->assertNotNull(theme_get_setting('features.favicon', $name));
   }
 
@@ -64,9 +64,11 @@ public function testNoDefaultConfig() {
    * Tests that the default logo config can be overridden.
    */
   public function testLogoConfig() {
+    /** @var \Drupal\Core\Extension\ThemeInstallerInterface $theme_installer */
+    $theme_installer = $this->container->get('theme_installer');
+    $theme_installer->install(['stark']);
     /** @var \Drupal\Core\Extension\ThemeHandler $theme_handler */
     $theme_handler = $this->container->get('theme_handler');
-    $theme_handler->install(['stark']);
     $theme = $theme_handler->getTheme('stark');
 
     // Tests default behaviour.
@@ -98,7 +100,7 @@ public function testLogoConfig() {
     $expected = '/' . $theme->getPath() . '/logo_relative_path.gif';
     $this->assertEquals($expected, theme_get_setting('logo.url', 'stark'));
 
-    $theme_handler->install(['test_theme']);
+    $theme_installer->install(['test_theme']);
     $theme_handler->setDefault('test_theme');
     $theme = $theme_handler->getTheme('test_theme');