[Users] Oauth2 not working with Microsoft Exchange

[Claudio Passerone]

Hello,
I tried to setup my Microsoft Exchange account that I have with my
organization using Oauth2, but I failed. I have Claws Mail 4.0.0 running
on Ubuntu 20.04 LTS. I followed the instructions found at
https://www.claws-mail.org/faq/index.php/Oauth2 and did all the steps,
until the end.

The instructions do not say it, but I assume I have to click on "Open
default browser with request" to obtain an authorization code to
enter in the configuration. The instructions say to use:

  Redirect URI: http://127.0.0.1:8888

However, when I click to open the default browser, I get an error
message saying that the URI is not the correct one. I had to select
https://login.microsoftonline.com/common/oauth2/nativeclient instead.
In this way the browser does not give any error message, I have to
login (I'm redirected to my organization login page), and afterwards I
simply get a blank page. There is nothing else I can do, and even the
source code of the page is empty. I don't understand what am I doing
wrong. Does anybody have the same problem, or is there a fix?

Thanks a lot,

Claudio