use craft\mail\Mailer;

return [
    'components' => [
        'mailer' => function() {
            $mailer = Craft::createObject([
                'class' => craft\mail\Mailer::class,
                'transport' => [
                    'class' => \Swift_SmtpTransport::class,
                    'host' => getenv('EMAIL_HOST'),
                    'username' => getenv('EMAIL_USERNAME'),
                    'password' => getenv('EMAIL_PASSWORD'),
                    'port' => getenv('EMAIL_PORT'),
                    'encryption' => 'tls',
                ],
            ]);

            // Attach SwiftMailer logger
            $mailer->getTransport()->registerPlugin(new \Swift_Plugins_Loggers_ArrayLogger());
            return $mailer;
        },
    ],
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