Before editing the question, I would probably edit the answer, and explain why it answers a slightly different question than the one which was asked (refering to the deleted comment and the edit). It is not unlikely that others, when trying to find information about related topics, find your answer still useful, even if it does not fit to the last version of ...


This is a tough one. One option would be to edit the question after getting the clarification in a comment. You can even use the edit description to note that the clarification edits were derived from a comment. If there's any dispute, mods can see deleted comments on a question and untangle the mess. If the comment/edit were wrong and there are good answers,...


Unless the user has enough reputation to see a deleted post, I don't think they will be able to see the response. However, I'm not sure what the current state in logic is around notifications - they may get a notification that you responded if it was processed before the deletion, but I don't know if the notification is revoked after the deletion.

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