diff --git a/core/modules/user/src/AccountForm.php b/core/modules/user/src/AccountForm.php
index bf05df4..b99a0b1 100644
--- a/core/modules/user/src/AccountForm.php
+++ b/core/modules/user/src/AccountForm.php
@@ -387,21 +387,21 @@ protected function flagViolations(EntityConstraintViolationListInterface $violat
    */
   public function submitForm(array &$form, FormStateInterface $form_state) {
     $account = $this->getEntity($form_state);
-    $new_email = $form_state->getValue('mail');
+    $new_mail = $form_state->getValue('mail');
+    $old_mail = $account->getEmail();
 
-    if(!$account->isNew() && $account->getEmail() !== $new_email && !\Drupal::currentUser()->hasPermission('administer users')) {
-      $old_email = $account->getEmail();
+    if (!$account->isNew() && $old_mail !== $new_mail && !$this->currentUser()->hasPermission('administer users')) {
 
       // Send a verification to the new email address.
-      $account->setEmail($new_email);
-      if(_user_mail_notify('mail_change_verification', $account, NULL)) {
+      $account->setEmail($new_mail);
+      if (_user_mail_notify('mail_change_verification', $account, NULL)) {
         // Send notification email to the old email address.
-        $account->setEmail($old_email);
+        $account->setEmail($old_mail);
         _user_mail_notify('mail_change_notification', $account);
       }
 
       // The user's email address will be updated after verification.
-      $form_state->setValue('mail', $old_email);
+      $form_state->setValue('mail', $old_mail);
 
       drupal_set_message($this->t('Your email address needs to be validated. Further instructions have been sent to your new email address.'), 'warning');
     }
diff --git a/core/modules/user/src/AccountSettingsForm.php b/core/modules/user/src/AccountSettingsForm.php
index c20a020..fb8fac2 100644
--- a/core/modules/user/src/AccountSettingsForm.php
+++ b/core/modules/user/src/AccountSettingsForm.php
@@ -305,44 +305,44 @@ public function buildForm(array $form, FormStateInterface $form_state) {
 
     $form['email_email_change_notification'] = array(
       '#type' => 'details',
-      '#title' => t('Email change notification'),
+      '#title' => $this->t('Email change notification'),
       '#collapsible' => TRUE,
       '#collapsed' => TRUE,
-      '#description' => t("Edit the email messages sent to users' old email address when the email address is changed.") . ' ' . $email_token_help,
+      '#description' => $this->t("Edit the email messages sent to users' old email address when the email address is changed.") . ' ' . $email_token_help,
       '#group' => 'email',
       '#weight' => 11,
     );
     $form['email_email_change_notification']['user_email_change_notification_subject'] = array(
       '#type' => 'textfield',
-      '#title' => t('Subject'),
+      '#title' => $this->t('Subject'),
       '#default_value' => $mail_config->get('mail_change_notification.subject'),
       '#maxlength' => 180,
     );
     $form['email_email_change_notification']['user_email_change_notification_body'] = array(
       '#type' => 'textarea',
-      '#title' => t('Body'),
+      '#title' => $this->t('Body'),
       '#default_value' => $mail_config->get('mail_change_notification.body'),
       '#rows' => 12,
     );
 
     $form['email_email_change_verification'] = array(
       '#type' => 'details',
-      '#title' => t('Email change verification'),
+      '#title' => $this->t('Email change verification'),
       '#collapsible' => TRUE,
       '#collapsed' => TRUE,
-      '#description' => t("Edit the email messages sent to users' new email address when the email address is changed.") . ' ' . $email_token_help,
+      '#description' => $this->t("Edit the email messages sent to users' new email address when the email address is changed.") . ' ' . $email_token_help,
       '#group' => 'email',
       '#weight' => 13,
     );
     $form['email_email_change_verification']['user_email_change_verification_subject'] = array(
       '#type' => 'textfield',
-      '#title' => t('Subject'),
+      '#title' => $this->t('Subject'),
       '#default_value' => $mail_config->get('mail_change_verification.subject'),
       '#maxlength' => 180,
     );
     $form['email_email_change_verification']['user_email_change_verification_body'] = array(
       '#type' => 'textarea',
-      '#title' => t('Body'),
+      '#title' => $this->t('Body'),
       '#default_value' => $mail_config->get('mail_change_verification.body'),
       '#rows' => 12,
     );
diff --git a/core/modules/user/src/Controller/UserController.php b/core/modules/user/src/Controller/UserController.php
index 018cfb5..9c4a667 100644
--- a/core/modules/user/src/Controller/UserController.php
+++ b/core/modules/user/src/Controller/UserController.php
@@ -71,7 +71,7 @@ public static function create(ContainerInterface $container) {
   }
 
   /**
-   * Returns the user password reset page.
+   * Provides a callback for user E-mail change page.
    *
    * @param int $uid
    *   UID of user requesting reset.
@@ -145,7 +145,7 @@ public function resetPass($uid, $timestamp, $hash) {
    *   UID of user requesting reset.
    * @param int $timestamp
    *   The current timestamp.
-   * @param string new_email
+   * @param string $new_mail
    *   The user's new email address.
    * @param string $hash
    *   Login link hash.
@@ -156,30 +156,29 @@ public function resetPass($uid, $timestamp, $hash) {
    * @throws \Symfony\Component\HttpKernel\Exception\AccessDeniedHttpException
    *   If the timestamp passed is in the future.
    */
-  public function changeEmail($uid, $timestamp, $new_email, $hash) {
-    $user = \Drupal::currentUser();
+  public function changeEmail($uid, $timestamp, $new_mail, $hash) {
     $account = $this->userStorage->load($uid);
 
-    // We need to set the new email here to validate the hash correctly, which is
-    // created using the new mail adress. We only save the account if the hash matches.
-    $account->setEmail($new_email);
-
+    // We need to set the new email here to validate the hash correctly,
+    // which is created using the new mail adress. We only save the account
+    // if the hash matches.
+    $account->setEmail($new_mail);
     $timeout = 24 * 60 * 60;
-    $current = $_SERVER['REQUEST_TIME'];
+    $current = REQUEST_TIME;
 
     if ($timestamp < $current) {
-      if($current - $timestamp > $timeout) {
+      if ($current - $timestamp > $timeout) {
         drupal_set_message(t('You have tried to use a one-time email address change link for %account that has expired -- your change of email address was not completed. Please visit your account edit page if you wish to attempt the change again.', array('%account' => $account->name)), 'error');
       }
-      else if ($user->id() && $user->id() != $account->id()) {
+      elseif ($this->currentUser()->id() && $this->currentUser()->id() != $account->id()) {
         drupal_set_message(t('You are currently logged in as %user, and are attempting to confirm an email address change for %account, which is not allowed. Please log in as %account and initiate a new change of email request.', array('%user' => $user->name, '%account' => $account->name)), 'error');
       }
-      else if ($hash != user_pass_rehash($account, $timestamp)) {
+      elseif ($hash != user_pass_rehash($account, $timestamp)) {
         drupal_set_message(t('There was a problem validating the used link. Please visit your account edit page and retry changing your email address.'), 'error');
       }
-      else if ($timestamp > $account->getLastLoginTime() && $timestamp < $current) {
+      elseif ($timestamp > $account->getLastLoginTime() && $timestamp < $current) {
         $account->save();
-        drupal_set_message(t('Your email address has been changed to %mail.', array('%mail' => $new_email)));
+        drupal_set_message(t('Your email address has been changed to %mail.', array('%mail' => $new_mail)));
       }
     }
     else {
diff --git a/core/modules/user/user.install b/core/modules/user/user.install
index 0c59cb7..ad523f8 100644
--- a/core/modules/user/user.install
+++ b/core/modules/user/user.install
@@ -1,5 +1,7 @@
 <?php
 
+use Symfony\Component\Yaml\Yaml;
+
 /**
  * @file
  * Install, update and uninstall functions for the user module.
@@ -88,13 +90,15 @@ function user_install() {
 
 
 /**
- * Update config for change mail notifications.
+ * Updates config for change mail notifications.
  */
 function user_update_8002() {
+  $mail_settings = Yaml::parse(file_get_contents(__DIR__ . '/config/install/user.mail.yml'));
+
   $mail_config = \Drupal::service('config.factory')->getEditable('user.mail');
-  $mail_config->set('mail_change_notification.body',"[user:display-name],\n\nA request to change your e-mail address has been made at [site:name]. In order to complete the change you will need to follow the instructions sent to your new e-mail address within one day.");
-  $mail_config->set('mail_change_notification.subject','E-mail change information for [user:display-name] at [site:name]');
-  $mail_config->set('mail_change_verification.body',"[user:display-name],\n\nA request to change your e-mail address has been made at [site:name]. You need to verify the change by clicking on the link below or copying and pasting it in your browser:\n\n[user:mail-change-login-url]\n\nThis is a one-time URL, so it can be used only once. It expires after one day. If not used, your e-mail address at [site:name] will not change.");
-  $mail_config->set('mail_change_verification.subject','E-mail change information for [user:display-name] at [site:name]');
+  $mail_config->set('mail_change_notification.body', $mail_settings['mail_change_notification']['body']);
+  $mail_config->set('mail_change_notification.subject', $mail_settings['mail_change_notification']['subject']);
+  $mail_config->set('mail_change_verification.body', $mail_settings['mail_change_verification']['body']);
+  $mail_config->set('mail_change_verification.subject', $mail_settings['mail_change_verification']['body']);
   $mail_config->save();
 }
diff --git a/core/modules/user/user.module b/core/modules/user/user.module
index 0246d24..cf58e5b 100644
--- a/core/modules/user/user.module
+++ b/core/modules/user/user.module
@@ -606,7 +606,7 @@ function user_pass_reset_url($account, $options = array()) {
  *   A unique URL that provides a one-time email change confirmation for the
  *   user.
  */
-function user_change_mail_url($account, $options = array()) {
+function user_change_mail_url($account, $options = []) {
   $timestamp = $_SERVER['REQUEST_TIME'];
   $langcode = isset($options['langcode']) ? $options['langcode'] : $account->getPreferredLangcode();
   $url_options = array('absolute' => TRUE, 'language' => \Drupal::languageManager()->getLanguage($langcode));