I think what happened is the link worked as long as the comment was still on the first page of your comment history, and the #fragment could jump down to it. Th

I think what happened is the link worked as long as the comment was still on the first page of your comment history, and the #fragment could jump down to it. Then once you made the comment in this discussion, it wasn’t within your comment history’s first page anymore, and the #fragment is invalid. I don’t know how you got that link, but, to avoid that issue, use URL pointed at by the “X days ago” link.