Editing questions from new users for formatting issues is a routine task here on SO, and most of the time I just fix the problem and move on.
Just now I spotted a question that began with a large bolded greeting and used
<br/> tags to force new lines instead of using double line breaks. I proceeded to edit the question, then composed a comment explaining how line-breaks work in markdown. Before posting it, I realised that there is a good argument for the comment being noise, since it does not directly pertain to the question.
Is it appropriate to leave a comment explaining what the OP did wrong instead of just silently editing the question (which could be confusing for the OP)?