Possible Duplicate:
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Appears on old questions that were marked as duplicates before the new closing overhaul. These notices were edited directly into the question by the Community user and could be freely edited and even removed. This has since been replaced, but questions that previously had it were not updated.
This question already has an answer here:
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The new default message that is shown to everyone when a question gets closed as a duplicate. It is an automatic box that is displayed and cannot be edited.
This question may already have an answer here:
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This message is shown to the author of the question only when it has a pending close-as-duplicate vote on it, until the question either gets closed or the duplicate vote expires.
This question is an exact duplicate of:
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Looks like this is a special case for when you close as a duplicate of another question that doesn't have any upvoted answers.
On normal sites, you can only vote to close as a duplicate if the other question has an answer (with a few exceptions). On Meta, however, any question can be closed as a duplicate of another question, no matter if it has answers or not. So naturally you'll see this possibility a lot more on Meta than on a main site.