Isn't there a feature for this now?
Most Helpful Guy
you cannot block an anonymous user. You can only prevent anonymous users from answering your questions.0
There is no way to block anonymous users. All you can do is not allow anonymous answers on your questions.
You can't which is why people harass others anonymous just don't allow anonymous users to answer your questions
If the poster in anonymous, you cannot block them because there's no visible username to block.
You can block ALL anonymous opinions from your questions.
You can also report all offensive/antagonistic posts, we encourage you guys to do so, but unfortunately there's no way to block anonymous without compromising the anonymity.
Our FAQ has this info as well :-)
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