I suspect you are right. I am having the same problem with Trojitá. It would seem helpful, given the popularity of GMail, to provide instructions/configuration so people could actually use KMail. I really prefer it to any other options. However, if I cannot my email, it isn't quite as useful.
It is a huge disappointment that KMail doesn't provide a simple to use wizard/fill in the blank form to connect to GMail.
Ditto for Apple's mail/tasks/notes/calendar (iCloud). Instructions for connecting to it are a bit hard to find (I found the WebDAV settings in one of the Apple/iThings fanboy listserv).
While I am toying with switching my main email to MyKolab, or self-hosting OX or Kolab, I, and a lot of other people, need to connect to GMail (the world's leading email service).
Your users should not have to spend hours trying to set up KMail! Both my (former) iPhone and Android phone connect out of the box, with only a few seconds required to put in my account information. KMail (and Trojitá) are both no-shows in this regard. I gave up using C++ years ago, and am not an expert on email services like you are, so there isn't much I can do to add a wizard to do whatever it takes to connect to non-Kolab email servers.
Kevin M. Coonan, M.D.
Minneapolis, MN
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Skype: kevin.coonan
kevin.coonan@gmail.com
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In the last analysis, we see only what we are ready to see, what we have been taught to see. We eliminate and ignore everything which is not a part of our prejudices.

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Jean-Martin Charcot (1825-1893)

On Mon, Feb 22, 2016 at 7:25 AM, Jan Kundrát via KDE Bugzilla <bugzilla_noreply@kde.org> wrote:

> https://bugs.kde.org/show_bug.cgi?id=359545
> Jan Kundrát <jkt@kde.org> changed:
> What |Removed |Added
> ----------------------------------------------------------------------------
> Resolution|--- |WAITINGFORINFO
> Status|UNCONFIRMED |NEEDSINFO
> --- Comment #2 from Jan Kundrát <jkt@kde.org> ---
> Please reopen when you have provided the requested information -- this is very
> likely GMail's security feature which allows you to perform some manual steps.
> --
> You are receiving this mail because:
> You reported the bug.