3.0.0

• [BC break] Change the base class of controllers to use the AbstractController (but extending the controllers is not officially supported anymore).
• [BC break] Remove the group feature
• [BC break] Change the base class for events to Symfony\Contracts\EventDispatcher\Event instead of Symfony\Component\EventDispatcher\Event
• [BC break] Remove the Symfony\Component\Security\Core\User\AdvancedUserInterface methods from our UserInterface
• [BC break] The ResettingListener now longer blocks password resetting requests based on the isAccountNonLocked method of the AdvancedUserInterface. Projects customizing isAccountNonLocked for that purpose should instead register their own listener for the FOSUserEvents::RESETTING_RESET_REQUEST event to set a response instead of processing the request.
• [BC break] Made \FOS\UserBundle\Model\User::serialize and \FOS\UserBundle\Model\User::unserialize final. Child classes needing to extend the serialization must override __serialize and __unserialize instead.
• [BC break] \FOS\UserBundle\Event\GetResponseNullableUserEvent no longer inherits from \FOS\UserBundle\Event\GetResponseUserEvent and \FOS\UserBundle\Event\UserEvent as that was breaking variance rules.
• [BC break] A few methods of FOS\UserBundle\Model\User now have return types (in methods where Symfony 6 requires them)
• [BC break] The legacy mailer based on SwiftMailer and symfony/templating is no longer used by default. Selecting a mailer service is now mandatory when using a feature needing the mailer.
• [BC break] Remove the legacy mailer based on SwiftMailer and symfony/templating. Use fos_user.mailer.twig_swift or a custom mailer service.
• Add support for Symfony 5.
• Add return types in most methods.
• Add autowiring support for FOS\UserBundle\Mailer\MailerInterface