When a user flags/votes to close your question as a duplicate, you'll see a dialog asking you to confirm whether it's a duplicate or not.

When you submit 'No', the dialog disappears, which is great. It is even hidden the next times you visit the question ... until another user flags/votes to close the question as a duplicate. Then it reappears. I don't like having to tell the system my opinion twice; I know I can just ignore the dialog, but it's still awkward.

_{Interestingly enough, if the duplicate flag/vote is retracted, the dialog disappears...}

When a user flags/votes to close your question as a duplicate, you'll see a dialog asking you to confirm whether it's a duplicate or not.

When you submit 'No', the dialog disappears, which is great. It is even hidden the next times you visit the question ... until another user flags/votes to close the question as a duplicate. Then it reappears; while that would make sense if a user proposes a new original, it is shown even when the same original is selected. 

I don't like having to tell the system twice that I don't think it's a duplicate. I know I can just ignore the dialog, it will go away eventually, but it's still rather awkward.

_{Interestingly enough, if the duplicate flag/vote is retracted, the dialog disappears...}