diff --git a/framework/core/src/Notification/NotificationMailer.php b/framework/core/src/Notification/NotificationMailer.php
index 02ac747dce..33722945a7 100644
--- a/framework/core/src/Notification/NotificationMailer.php
+++ b/framework/core/src/Notification/NotificationMailer.php
@@ -64,7 +64,7 @@ function (Message $message) use ($blueprint, $user) {
      *     html: string
      * }
      */
-    protected function getEmailViews(MailableInterface $blueprint): array
+    protected function getEmailViews(MailableInterface&BlueprintInterface $blueprint): array
     {
         $views = $blueprint->getEmailViews();