OpenID Connect/OAuth2 with KDE's Gitlab
With KDE’s contributor account management moving from the deprecated identity.kde.org and my.kde.org systems to Gitlab as the central identity provider we need to adapt all applications requiring a login to use OpenID Connect/OAuth2 for authentication. While that is largely done for the web-based ones, native client applications remain a challenge.
Before we start: This is not a definitive guide on how to set things up properly. It is rather my current understanding on how things could be done, and a request for review/feedback by people with more experience on this subject.