Why can't I upvote this answer?
I tried to upvote this answer but my vote doesn't seem to register.
Maybe it is because it is owned by System, but then, there are other answers owned by System that already have upvotes.
Note that I don't have any problems to upvote other answers on the same question.
(Unrelated observation: The link seems to position the page at the end of the question instead of the beginning.)