diff --git a/core/modules/locale/src/LocaleConfigManager.php b/core/modules/locale/src/LocaleConfigManager.php
index e67f3bc..facdaeb 100644
--- a/core/modules/locale/src/LocaleConfigManager.php
+++ b/core/modules/locale/src/LocaleConfigManager.php
@@ -603,10 +603,12 @@ public function updateConfigTranslations(array $names, array $langcodes = []) {
             $count++;
           }
         }
-        elseif (locale_is_translatable($langcode)) {
+        elseif (locale_is_translatable($langcode) && $name != 'system.site') {
           // If the language code is the active storage language, we should
           // update. If it is English, we should only update if English is also
-          // translatable.
+          // translatable. The system.site configuration is special because it
+          // is written during installation using the langcode at installation
+          // time.
           $active = NestedArray::mergeDeepArray([$active, $processed], TRUE);
           $this->saveTranslationActive($name, $active);
           $count++;
diff --git a/core/modules/system/src/Tests/Installer/InstallerTranslationMultipleLanguageTest.php b/core/modules/system/src/Tests/Installer/InstallerTranslationMultipleLanguageTest.php
index a608cad..dcde753 100644
--- a/core/modules/system/src/Tests/Installer/InstallerTranslationMultipleLanguageTest.php
+++ b/core/modules/system/src/Tests/Installer/InstallerTranslationMultipleLanguageTest.php
@@ -51,13 +51,29 @@ protected function getPo($langcode) {
 
 msgid "Language"
 msgstr "Language $langcode"
+
+#: Testing site name configuration during the installer.
+msgid "Drupal"
+msgstr "Drupal"
 ENDPO;
   }
 
   /**
+   * {@inheritdoc}
+   */
+  protected function installParameters() {
+    $params = parent::installParameters();
+    $params['forms']['install_configure_form']['site_name'] = 'SITE_NAME_' . $this->langcode;
+    return $params;
+  }
+
+  /**
    * Tests that translations ended up at the expected places.
    */
   public function testTranslationsLoaded() {
+    // Ensure the title is correct.
+    $this->assertEqual('SITE_NAME_' . $this->langcode, \Drupal::config('system.site')->get('name'));
+
     // Verify German and Spanish were configured.
     $this->drupalGet('admin/config/regional/language');
     $this->assertText('German');