diff --git a/core/includes/bootstrap.inc b/core/includes/bootstrap.inc
index 296436394e..fb7effe49a 100644
--- a/core/includes/bootstrap.inc
+++ b/core/includes/bootstrap.inc
@@ -461,7 +461,8 @@ function watchdog_exception($type, Exception $exception, $message = NULL, $varia
  *   Use \Drupal::service('messenger')->addMessage() instead.
  */
 function drupal_set_message($message = NULL, $type = 'status', $repeat = FALSE) {
-  // Workaround for code that can not check if the service exists.
+  // This function might be called in the early installer, so we check for now
+  // whether the service exists.
   /* @var \Drupal\Core\Messenger\MessengerInterface $messenger */
   if (\Drupal::hasService('messenger')) {
     $messenger = \Drupal::service('messenger');
@@ -470,7 +471,7 @@ function drupal_set_message($message = NULL, $type = 'status', $repeat = FALSE)
     $messenger = new LegacyMessenger();
   }
   $messenger->addMessage($message, $type, $repeat);
-  return $messenger->getMessages();
+  return $messenger->all();
 }
 
 /**
@@ -504,10 +505,10 @@ function drupal_set_message($message = NULL, $type = 'status', $repeat = FALSE)
  */
 function drupal_get_messages($type = NULL, $clear_queue = TRUE) {
   /** @var \Drupal\Core\Messenger\MessengerInterface $messenger */
-  if (($messenger = \Drupal::hasService('messenger') ? \Drupal::service('messenger') : NULL) && $messages = $messenger->getMessages()) {
+  if (($messenger = \Drupal::hasService('messenger') ? \Drupal::service('messenger') : NULL) && $messages = $messenger->all()) {
     if ($type) {
       if ($clear_queue) {
-        $messenger->deleteMessagesByType($type);
+        $messenger->deleteByType($type);
       }
       if (isset($messages[$type])) {
         return [$type => $messages[$type]];
@@ -515,7 +516,7 @@ function drupal_get_messages($type = NULL, $clear_queue = TRUE) {
     }
     else {
       if ($clear_queue) {
-        $messenger->deleteMessages();
+        $messenger->deleteAll();
       }
       return $messages;
     }
diff --git a/core/lib/Drupal/Core/Messenger/LegacyMessenger.php b/core/lib/Drupal/Core/Messenger/LegacyMessenger.php
index 7eeee053ab..1708a0691c 100644
--- a/core/lib/Drupal/Core/Messenger/LegacyMessenger.php
+++ b/core/lib/Drupal/Core/Messenger/LegacyMessenger.php
@@ -44,28 +44,28 @@ public function addWarning($message, $repeat = FALSE) {
   /**
    * {@inheritdoc}
    */
-  public function getMessages() {
+  public function messages() {
     return _drupal_get_messages(NULL, FALSE);
   }
 
   /**
    * {@inheritdoc}
    */
-  public function getMessagesByType($type) {
+  public function messagesByType($type) {
     return _drupal_get_messages($type, FALSE);
   }
 
   /**
    * {@inheritdoc}
    */
-  public function deleteMessages() {
+  public function deleteAll() {
     return _drupal_get_messages(NULL, TRUE);
   }
 
   /**
    * {@inheritdoc}
    */
-  public function deleteMessagesByType($type) {
+  public function deleteByType($type) {
     return _drupal_get_messages($type, TRUE);
   }
 
@@ -100,9 +100,6 @@ function _drupal_set_message($message = NULL, $type = 'status', $repeat = FALSE)
 }
 
 /**
- * The old implementation of drupal_get_messages
- *
- * /**
  * Returns all messages that have been set with drupal_set_message().
  *
  * @param string $type
diff --git a/core/lib/Drupal/Core/Messenger/MessengerInterface.php b/core/lib/Drupal/Core/Messenger/MessengerInterface.php
index 8e15dc19c8..941a3eebcc 100644
--- a/core/lib/Drupal/Core/Messenger/MessengerInterface.php
+++ b/core/lib/Drupal/Core/Messenger/MessengerInterface.php
@@ -27,6 +27,8 @@
   /**
    * Adds a new message to the queue.
    *
+   * The messages will be displayed in the order they got added later.
+   *
    * @param string|\Drupal\Component\Render\MarkupInterface $message
    *   (optional) The translated message to be displayed to the user. For
    *   consistency with other messages, it should begin with a capital letter
@@ -95,7 +97,7 @@ public function addWarning($message, $repeat = FALSE);
    *   types are either self::TYPE_STATUS, self::TYPE_WARNING, or
    *   self::TYPE_ERROR.
    */
-  public function getMessages();
+  public function all();
 
   /**
    * Gets all messages of a certain type.
@@ -106,12 +108,12 @@ public function getMessages();
    *
    * @return string[]|\Drupal\Component\Render\MarkupInterface[]
    */
-  public function getMessagesByType($type);
+  public function messagesByType($type);
 
   /**
    * Deletes all messages.
    */
-  public function deleteMessages();
+  public function deleteAll();
 
   /**
    * Deletes all messages of a certain type.
@@ -120,6 +122,6 @@ public function deleteMessages();
    *   The messages' type. Either self::TYPE_STATUS, self::TYPE_WARNING, or
    *   self::TYPE_ERROR.
    */
-  public function deleteMessagesByType($type);
+  public function deleteByType($type);
 
 }