Issue #3307736 by catch, alexpott: EmailValidator defaults to 'loose' mode which is deprecated in Symfony 6.2

core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/EmailConstraint.php

@@ -28,7 +28,7 @@ class EmailConstraint extends Email {
    * {@inheritdoc}
    */
   public function validatedBy() {
-    return '\Symfony\Component\Validator\Constraints\EmailValidator';
+    return EmailValidator::class;
   }
 
 }

core/lib/Drupal/Core/Validation/Plugin/Validation/Constraint/EmailValidator.php

@@ -0,0 +1,25 @@
+<?php
+
+namespace Drupal\Core\Validation\Plugin\Validation\Constraint;
+
+use Symfony\Component\Validator\Constraints\Email;
+use Symfony\Component\Validator\Constraints\EmailValidator as SymfonyEmailValidator;
+
+/**
+ * Email constraint.
+ *
+ * Overrides the symfony validator to use the HTML 5 setting.
+ *
+ * @internal Exists only to override the constructor to avoid a deprecation
+ *   in Symfony 6, and will be removed in drupal:11.0.0.
+ */
+final class EmailValidator extends SymfonyEmailValidator {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function __construct(string $defaultMode = Email::VALIDATION_MODE_HTML5) {
+    parent::__construct($defaultMode);
+  }
+
+}