It changes the rendering of package-info buffers such that, instead of
displaying something like:

  Name        : coreutils
  Version     : 8.23
  Synopsis    : Core GNU utilities (file, text, shell)
  ...

it first displays the important info in a visible heading, and then goes
on with the other fields unchanged:

  coreutils 8.23
  Core GNU utilities (file, text, shell)

  Outputs:
    out       Delete
  ...

On X11, the package name and version are displayed in a large
variable-width font, and the synopsis is displayed in a slightly smaller
font.

Ludo’.