I'm not sure if this is a bug or not, but I've seen it several times over the past few days. Occasionally there will be one of these comments under a question:
possible duplicate of ...
But there are no close votes yet. I imagine this could be caused in the case where the close-voter retracted their close vote, but if so, shouldn't this also remove the comment if they were the only one? (This makes me wonder what should happen if someone else has voted in the meantime.)
I saw this today on this question - however I voted to close, so it doesn't look like a repro right now, except that it should have two close votes if the commenter voted to close and so did I.
Not asking for anything to change, in fact I'm glad the comment was still there or I wouldn't have searched for a duplicate either, just wondering if there is any other reason this scenario would happen, other than the original close-voter retracting their close vote?