diff -u b/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
--- b/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -461,7 +461,7 @@
  *   Use \Drupal::service('messenger')->addMessage() instead.
  */
 function drupal_set_message($message = NULL, $type = 'status', $repeat = FALSE) {
-  // This function might be called in the early installer, so we check for now
+  // This function might be called early on in the installer, so we check
   // whether the service exists.
   /* @var \Drupal\Core\Messenger\MessengerInterface $messenger */
   if (\Drupal::hasService('messenger')) {
diff -u b/core/lib/Drupal/Core/Messenger/LegacyMessenger.php b/core/lib/Drupal/Core/Messenger/LegacyMessenger.php
--- b/core/lib/Drupal/Core/Messenger/LegacyMessenger.php
+++ b/core/lib/Drupal/Core/Messenger/LegacyMessenger.php
@@ -125,7 +125,7 @@
  * @see status-messages.html.twig
  *
  * @internal
- * @deprecated Deprecated as of Drupal 8.2.
+ * @deprecated Deprecated as of Drupal 8.4.
  *   Use \Drupal::service('messenger')->getMessages() or
  *   \Drupal::service('messenger')->getMessagesByType() instead.
  */