What is MO's exact policy on answering or not answering off-topic questions? Assuming there is some well-defined policy. My guess is: you are allowed to answer off-topic questions and if somebody provides a precise, detailed answer to an off-topic question, you should not downvote them. Downvote this post if you disagree.

EDIT: I should have clarified what I mean by off-topic. I mean the following situation: a person gives an answer, after they did this, the question is put on hold as off-topic (e.g. see here). Does their answer also become off-topic, or what?