This question already has an answer here:
- Introduce a “general reference” close reason 12 answers
I just came across this question on English.SE. The banner says it was closed by a moderator as "general reference", which is not one of the 5 standard close reasons (duplicate, off-topic, too broad, unclear what you're asking, and primarily opinion based). It is similar to a current ELU off-topic close reason, just displayed in a different way.
Of course, the question was closed before the beginning of time, so the rules were probably different back then.
Were closed questions previously displayed with the off-topic close reason shown at the top of the banner (rather than just "off-topic")? If so, why? If not, why was the close reason shown as "general reference" in this case?