For all reasons mentioned in the article, I wouldn’t post such a question on Stackoverflow. It doesn’t fit. And I see their reasoning. Just raise an issue in the CoreWCF issue tracker. What’s the worst thing to happen?
The CoreWCF folks would be delighted to have a reproducible example, and they are best suited for answering the question. They have written CoreWCF after all! And if you don’t feel comfortable with raising issues? There’s also a Discussion feature on GitHub, where you can ask more free form questions.
And once you fixed or analyzed the issue with the CoreWCF team, you could write a blog post about it and share it with anyone having a similar issue.
That’s how I do these things.