Even the whoosh sound isn’t a reliable indicator of a mail being sent. I now have to check each time I send mail to be sure it actually did send. I have multiple emails a day that do not get sent.
I understand that open-source software is known to have issues of not having enough development resources to address things… but this is something I paid for. And it is failing in one of its most basic tasks: It’s an email client that doesn’t send emails.
If you can’t deliver the basic reliably, then maybe this shouldn’t be charged for at all.