Kmail doesn't send email using Gmail

[Aldo Latino]

Hello everyone,
I am really enjoying using Kontact and in particular Kmail and KOrganizer, but 
there is still a problem that annoys me. I am referring to this particular 
bug: https://bugs.kde.org/show_bug.cgi?id=421664

After firing up Kontact I am able to send email via a Gmail account, but after 
a while (I haven't calculated the timing) Kmail is not able to send email 
anymore, and the email stops in the outgoing folder, awaiting for something.

Sometimes it is enough to restart Kontact in order to send those emails, or I 
have to restart Akonadi. But this is really annoying.

The problem seems to be present only in my Gmail account. In my other email 
account the email are being sent correctly.

The Gmail IMAP account is working correctly in the other aspects, i.e. 
browsing folders and receiving emails.

The Gmail SMTP settings seem to be correctly configured:
- smtp.gmail.com
- required authentication
- username with the complete email address
- using STARTTLS, port 587 and XOAUTH2

I am using Kontact 5.16.2 and KDE neon User Edition, with all the updates 
installed.

Have you noticed this behaviour in your Kontact/Kmail installation?

-- 
Aldo Latino
aldolat at gmail.com
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