Using watchdog_mailer leads to the following error in symfony_mailer:
Error: Call to a member function fromArray() on null in Drupal\symfony_mailer\MailManagerReplacement->mail() (Zeile 89 in /web/modules/contrib/symfony_mailer/src/MailManagerReplacement.php)
#0 /web/modules/contrib/watchdog_mailer/src/Logger/WatchdogMailer.php(140): Drupal\symfony_mailer\MailManagerReplacement->mail()
As this similar issue says, the reason is that hook_mails needs to be implemented accordingly:
💬
fromArray() on null in MailManagerReplacement->mail()
Closed: works as designed
This is the root cause: ✨ Handle case where hook_mail() does not exist Active
Closed: cannot reproduce
3.0
Code
Okay this is strange, hook_mail already exists:
https://git.drupalcode.org/issue/watchdog_mailer-3457063/-/blob/3457063-...
So no idea yet, why Symfony Mailer throws this error?!
Ok seems like I just had to clear caches after installation. That's even stranger.