🇵🇱Poland robert.kandzia
Hi! I had the same message in my app. In my case, I send emails to a queue.
I analyzed the classes MessageNotifierBase and Email code for the send(), deliver() and postSend() methods. I reached the place that returns boolean - this is the deliver() method. It seems to me that a value should be passed in the $result['result'] parameter, where it returns TRUE, FALSE or NULL. And there is an isset() check that returns TRUE or FALSE.
In my case $result['result'] returns NULL because the message is queued (not sent immediately). So in postSend() is passed NULL and it does not enter the condition ($result === FALSE).
This should solve the problem of sending emails when using a queue, e.g. queue_mail module.