@dimalifragis, it may not specifically be a job for wpForo, but it's something wpForo could do. Adding a forum with a lot of users introduces all kinds of email complications. If it queued notifications or could add them to a BCC line instead of sending so many emails via PHP all at once, it would help tremendously.

@dimalifragis, that's not a magic pill, unfortunately. With GD Mail Queue installed and working on my staging site, here are 2 tests with and without 1,000 subscribers. Quite a substantial difference.

@sofy It is not as simple as that, i'm afraid.

For example you NEED to excempt New Signups and Lost Password requests/emails from the queue. Any queue.

And you can't do that with that plugin you suggest, while GD Mail Queue offers all that with a snippet.

GD Mail Queue is much much more advanced.

The snippet i mentioned:

add_filter('gdmaq_mailer_add_to_queue', 'custom__gdmaq_mailer_add_to_queue', 10, 3);
function custom__gdmaq_mailer_add_to_queue($add, $email, $type) {
  $dont_add = array('wp_password_change_notification', 'wp_new_user_notification_admin', 'wp_email_change_confirmation', 'wp_new_user_notification', 'wp_recovery_mode_email', 'wp_retrieve_password_message');
  if (in_array($type, $dont_add)) {
    $add = false;
  }
  return $add;
}