When is it (and isn't) acceptable to edit?
Say for instance, I have upvoted an answer but wrote another answer for more reference. But OP commented on the answer I upvoted that OP previously accepted as answer but unaccepted since OP thinks the answer did not work. So I wrote a comment that it actually works. See here.
Is it okay though to just edit the answer if the modification that will be done is substantial?
Update I think this post is a possible duplicate of this post: Etiquette: when is it acceptable to edit anothers' answer?. I did not see it before writing this post although it did not appear as related question then.