Referring to this answer as an example: https://english.stackexchange.com/a/119687/47377
While the answer isn't strictly relevant, the user has obviously put some effort into researching it. On the other hand, it really doesn't answer the question. As it's a new user, I don't want to put them off by downvoting.
I've come across other examples of tangential answers while reviewing, so thought I would ask if there is any guidance on how to deal with them.