Michael Gallagher - NOAA Affiliate <michael.r.gallagher@noaa.gov>
writes:

> The purpose for me is to clearly delineate the
> text/code from the line numbers in a way that makes it easier to grok the
> text being displayed. My brain sees the numbers as part of the code with the
> current formatting of display-line-numbers, but maybe I'm uniquely
> incapable. 

Does it help to customize the `line-number' face to something that has a
different background colour than the main text?  For instance, setting
the background colour to black gives me this: