Having the Messenger component is not enough for the emails to be sent via a bus. If you want to disable sending emails via the messenger, you need to remove the configuration for the SendEmailMessage class in your configuration.

Having the Messenger component is not enough for the emails to be sent via a bus. If you want to disable sending emails via the messenger, you need to remove the configuration for the SendEmailMessage class in your configuration.

Thanks, that really helped in a project with Symfony dependencies locked to 4.4 and symfony/mailer:^5.4.

We wanted to send mails asynchronously in prod and asynchronously in dev and test, so that we didn't have to call messenger:consume during tests to send emails. But we weren't able to use message_bus: false since it requires symfony/framework-bundle >= 5.1.

So we used this config:

# config/packages/messenger.yaml
framework:
    messenger:
        # …

        transports:
            async_import: '%env(MESSENGER_TRANSPORT_DSN)%'
            async_mailer: '%env(MESSENGER_TRANSPORT_DSN)%'

        routing:
            'App\Message\PriceImport': async_import

# config/packages/prod/messenger.yaml
framework:
    messenger:
        routing:
            'App\Message\PriceImport': async_import
            # use “…SendEmailMessage” only on prod environments,
            # so that emails are sent asynchronously on prod,
            # and synchronously on other environments
            'Symfony\Component\Mailer\Messenger\SendEmailMessage': async_mailer