diff --git a/core/modules/config_translation/src/Tests/ConfigTranslationUiTest.php b/core/modules/config_translation/src/Tests/ConfigTranslationUiTest.php
index 3d0741b..7e509a8 100644
--- a/core/modules/config_translation/src/Tests/ConfigTranslationUiTest.php
+++ b/core/modules/config_translation/src/Tests/ConfigTranslationUiTest.php
@@ -728,7 +728,7 @@ public function testTextFormatTranslation() {
     // security vulnerabilities.
     $config_factory
       ->setOverrideState(FALSE)
-      ->get('config_translation_test.content')
+      ->getEditable('config_translation_test.content')
       ->set('content.format', 'full_html')
       ->save();
 
diff --git a/core/modules/locale/src/Tests/LocaleUpdateBase.php b/core/modules/locale/src/Tests/LocaleUpdateBase.php
index 37d4d78..4ca566b 100644
--- a/core/modules/locale/src/Tests/LocaleUpdateBase.php
+++ b/core/modules/locale/src/Tests/LocaleUpdateBase.php
@@ -53,7 +53,7 @@ protected function setUp() {
     // Update module should not go out to d.o to check for updates. We override
     // the url to the default update_test xml path. But without providing
     // a mock xml file, no update data will be found.
-    \Drupal::config('update.settings')->set('fetch.url', _url('update-test', array('absolute' => TRUE)))->save();
+    $this->config('update.settings')->set('fetch.url', _url('update-test', array('absolute' => TRUE)))->save();
 
     // Setup timestamps to identify old and new translation sources.
     $this->timestampOld = REQUEST_TIME - 300;
@@ -63,7 +63,7 @@ protected function setUp() {
 
     // Enable import of translations. By default this is disabled for automated
     // tests.
-    \Drupal::config('locale.settings')
+    $this->config('locale.settings')
       ->set('translation.import_enabled', TRUE)
       ->save();
   }
@@ -77,7 +77,7 @@ protected function setUp() {
    */
   protected function setTranslationsDirectory($path) {
     file_prepare_directory($path, FILE_CREATE_DIRECTORY);
-    \Drupal::config('locale.settings')->set('translation.path', $path)->save();
+    $this->config('locale.settings')->set('translation.path', $path)->save();
   }
 
   /**
@@ -173,7 +173,7 @@ protected function makePoFile($path, $filename, $timestamp = NULL, array $transl
    * imported.
    */
   protected function setTranslationFiles() {
-    $config = \Drupal::config('locale.settings');
+    $config = $this->config('locale.settings');
 
     // A flag is set to let the locale_test module replace the project data with
     // a set of test projects which match the below project files.
diff --git a/core/modules/simpletest/src/InstallerTestBase.php b/core/modules/simpletest/src/InstallerTestBase.php
index 09a71cb..339d3b1 100644
--- a/core/modules/simpletest/src/InstallerTestBase.php
+++ b/core/modules/simpletest/src/InstallerTestBase.php
@@ -160,7 +160,7 @@ protected function setUp() {
 
     // Manually configure the test mail collector implementation to prevent
     // tests from sending out e-mails and collect them in state instead.
-    $config->get('system.mail')
+    $config->getEditable('system.mail')
       ->set('interface.default', 'test_mail_collector')
       ->save();
 
diff --git a/core/modules/simpletest/src/KernelTestBase.php b/core/modules/simpletest/src/KernelTestBase.php
index 84c1f42..99dfa76 100644
--- a/core/modules/simpletest/src/KernelTestBase.php
+++ b/core/modules/simpletest/src/KernelTestBase.php
@@ -480,7 +480,7 @@ protected function disableModules(array $modules) {
     // Unset the list of modules in the extension handler.
     $module_handler = $this->container->get('module_handler');
     $module_filenames = $module_handler->getModuleList();
-    $extension_config = $this->container->get('config.factory')->get('core.extension', TRUE);
+    $extension_config = $this->config('core.extension');
     foreach ($modules as $module) {
       unset($module_filenames[$module]);
       $extension_config->clear('module.' . $module);
diff --git a/core/modules/system/tests/modules/form_test/form_test.services.yml b/core/modules/system/tests/modules/form_test/form_test.services.yml
index 472e0bc..24513a6 100644
--- a/core/modules/system/tests/modules/form_test/form_test.services.yml
+++ b/core/modules/system/tests/modules/form_test/form_test.services.yml
@@ -1,6 +1,7 @@
 services:
   form_test.form.serviceform:
     class: Drupal\form_test\FormTestServiceObject
+    arguments: ['@config.factory']
   form_test.event_subscriber:
     class: Drupal\form_test\EventSubscriber\FormTestEventSubscriber
     tags: