reverted:
--- b/src/EventSubscriber/SendgridIpPoolNameSubscriber.php
+++ a/src/EventSubscriber/SendgridIpPoolNameSubscriber.php
@@ -42,7 +42,7 @@
   /**
    * {@inheritdoc}
    */
+  public static function getSubscribedEvents() {
-  public static function getSubscribedEvents(): array {
     return [
       SendgridEvents::SEND => ['onSendgridSend'],
     ];
only in patch2:
unchanged:
--- a/sendgrid.info.yml
+++ b/sendgrid.info.yml
@@ -1,7 +1,7 @@
 name: Sendgrid
 type: module
 description: Allows site to send emails using Sendgrid email service.
-core_version_requirement: ^8.9 || ^9 || ^10
+core_version_requirement: ^8.9 || ^9 || ^10 || ^11
 package: Mail
 configure: sendgrid.settings_form
 dependencies: