In particular new users sometimes ask a question that contains multiple subquestions which are better off as separate questions.
- How can we identify when such a question is too broad?
- How should experienced users deal with this?
A few rules of thumb:
Questions should only be asked together if their answers (if asked separately) can be expected to strongly overlap. Otherwise, they should be split.
Answers to a question should be directly comparable, and thus it should not happen that there is a best answer to one subquestion and another best answer to another subquestion. In the latter case, they should be split.
If you can answer only one subquestion to a question, it should be split.
If a question is asking to identify multiple fonts, styles, etc., it should be split.
In general, do not be overcautious with this: If you think that a question is better off as two separate questions, you are very likely right.
If there is at least one subquestion that is not closeworthy for other reasons, edit it immediately (or suggest an edit, if you do not have the reputation). There is nothing to be gained from waiting for the asker or others to perform the edit – it only increases the risk that somebody answers the question in the meantime.
Select the surviving subquestion by the following criteria (in order of priority):
Leave a comment explaining what you did, e.g., as follows:
As this site follows a strict question-and-answer format, there should be only one distinct question per question. I therefore took the liberty to remove your second question; feel free to ask it separately.
If all answers address the same subquestion, edit the question immediately to contain only that subquestion. Leave a comment similar as above.
In all other cases, you have to make a judgement call: Can this be resolved with a few minor edits and without invalidating large parts of existing answers? If not, vote to close as too broad. Leave a comment explaining your choice and possibly encourage the asker to narrow down their question. Keep in mind though that somebody answering a case of multiple questions per question has to accept the risk of their answer being invalidated by edits to the question.