Incorrect tag used to zap a question by the golden badge hammer

Question

I found this strange thing which is IMHO a bug:

The problem is that egreg zapped the question using his golden xetex badge. However, the question isn't tagged xetex, it had the tag but lost it before egreg voted on it. Sure egreg could zap the question anyways using his golden symbols badge.

The question is, whether the system used the correct golden badge and displayed the wrong one, or used the wrong one directly. Or is it status-bydesign that the original tags are considered when zapping the question by the golden badge hammer?

Answer 1

The notorious dupehammer gives superpowers to learned members of the community, but here are the rules:

• You can instantly close as a duplicate any question that was originally asked with a tag you have a gold badge for.
• You can instantly reopen any question closed as a duplicate that was originally asked with a tag you have a gold badge for.
• You can only close or reopen a given question once (this hasn't changed).
• If you get in a fight with someone over whether a question should be closed, moderators will be notified and they'll hit everyone with hammers lock everything down and tell you to go home.

The first point is emphasized later in the same linked "rule-post":

... If a question has a tag where you have a gold badge, and it was part of the original set of tags applied to the question, you can mark it as a duplicate with a single vote.

Therefore this is, as you mentioned, status-bydesign.