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political downvoting unrelated to a question?
I thought i was once advised that if I saw i'd been hit with what looks very much like a drive-by downvoter, like a few downvotes in one minute, then I should flag one of the questions and include a note that it and 2 others have just been downvoted.. and a moderator can look at it.
I just looked at the comments on flags i've made, one time I flagged a question or answer for the above reason which I stated, and the flag was declined on the basis that it didn't require moderator intervention.