I identified https://scifi.stackexchange.com/questions/17795/who-is-glados-saying-goodbye-to-in-portal-2 as a duplicate of gaming.stackexchange's Who is GLaDOS's “only friend” as soon as it was posted.
My first intent was to answer it with a link to the question because I think it's a great answer and I don't see what to add, but my answer was automatically converted into a comment as "Trivial answer converted to comment".
What should we do in that case? Close the question? make a copy-paste in a citation block?