No mail with symfony_mailer

I fix the patch.
Some wrong if conditions preventing save messages into mail safety table.

this is the patch for 8.2 version

Sorry, the patch is wrong.
this is the right, i hope

I can conform this works on 8.x-1.2
- Apply patch
- Clear caches (drush cr)
- Visit Settings > System > Mailer (/admin/config/system/mailer)
- Edit *All* (/admin/config/system/mailer/policy/_)
- From the dropdown, select 'Mail Safety' and add it

Thanks for the patch! Also works with 2.0. (#13)

A small note is that the patch forces all mails to not be sent when not using a/the default mail address by setting setTransportDsn as null. I had to make a copy of the patch and remove that part (+ the setReplyTo setting that is there for some reason).

Thanks for the patch, it is a valuable POC. Also for #15.

The adjuster approach has the downside though, that i must add an adjuster.

What i want as a site owner is sth like a simple config override setting to set in all dev environments and when i see that setting, i have no fear that a customer gets an ouch mail (which is the promise of this module).

Maybe leveraging hook_mailer_alter helps here.

Feedback from AdamPS (Maintainer of Drupal Symfony Mailer) in the related issue:

The patch on #3267796: No mail with symfony_mailer seems like the wrong approach - as you say it requires adding an adjuster. Presumably the module previously used hook_mail_alter() and it should now use the new hooks and throw a SkipSending.