For a question this is very worrisome for me. Posting that in a comment may well be fine, but by editing it into the question this is, more or less, the same as editing code in my mind (which is a big no no for questions, and should be met with a lot of scrutiny in answers). The edits to the code to turn it from an extracted snippet to a complete example may well change some of the semantics, thus leading another reader to believe the problem is due to something that is not in fact representative of the position the OP is in.
By posting a comment it's clear that this is one reader's attempt at replicating the problem, and that there is a possibility of deviations from the OP's actual code. It can still be helpful, but the little bit of skepticism is allowed to remain. If the OP feels it adequately represents their actual situation, they can edit it into the question themselves.
For an answer, I'm somewhat less opposed to the idea, but I would still rather see it as a comment, simply because of the likelihood of some semantic change in the answer. I would only approve the edit if I was comfortable enough in my understanding of the answer to feel that the added link adequately represents the answer, and that it doesn't alter it's semantics in any way.