Just to close the topic: I finished what I planned for the forked QtScrobbler-project. I changed the workflow, so that if you did not provide correct credentials for your favourite submission-site (last.fm, libre.fm ..), then the progress-dialog will be closed and you will see immediately the error in the ui (not just log). Because before the user could wait until the cows come home – and I found this really annoying, especially when I set up QtScrobbler on a new system, mistyped or forgot to set the credentials at all.
Besides: also cleaned the code a little bit with the help of cppcheck 😉
The repository: https://github.com/marcelpetrick/QTScrobbler
All in all it was a nice experience: set up GitHub, clone the repository, work into a medium large project, try to fix an error without breaking the remaining functionality ..
I do not fully agree to the original code of conduct for style and includes. But as long as it is comprehensive ..