While reviewing the First Posts queue, I came across this answer where the new user recommends a keyboard short-cut which closes the current window. I down-voted the answer and left a comment.
I searched for relevant posts on meta and Should potentially “Dangerous” answers be flagged/deleted? is the closest I could find. The consensus was to flag such posts for the moderator's attention.
However, I don't think this answer is actually dangerous; an alert user wouldn't be caught out by it and it's not the end of the world if the window did close since AFAIK Chrome keeps track of closed tabs and windows.
I'm wary of wasting a moderators' time but I thought I'd post here to see what other super users think.