If you use the ContentByLable macro you get a lovely list of pages. Looks good.
If there are no pages with the label you get a <div> with a message saying that there are no pages with that label. A big gray <div> that doesn't fit properly in say a table and that looks like heck in a mobile page.

What I want is to get rid of that message ie. if there are no pages, then nothing is shown:

I can modify the html in 'edit' mode but obviously that is lost when I publish. Any ideas?