There is a question that is marked as a duplicate and my opinion is that it is not.
I would like to ask how can I point it out? Should I flag it for moderator's attention and say my opinion or should I do something else?
At the moment I have written a comment but most people (if not all) that have marked the question won't be able to see it. That will only happen if by any chance they visit the question again, which is highly unlikely.
Until you have the privilege to vote-to-close or reopen, you're left to your own devices to persuade the community. Here are some options (in order of preference):
Post a comment in the thread in question to get the attention of some of the users who voted to close.
Visit the chat room (of course, once you have the chitter-chatter privilege) and discuss with the eager-to-listen folks the motivation behind your request. Most people there have the privilege to cast re-open votes and may be persuaded to do such.
Post a question on Meta.TeX.SE, since it is suitable here - asking questions about the main site using the discussion meta-tag. Users can then contribute their ideas in the form of answers until some community census is reached.
Flag for moderator attention stating your case. It may be that the mod takes up option (2) before doing anything.
