In comic book option to setup a shadow for double page layouts

Is your feature request related to a problem? Please describe. In CDisplayEx there is an option for putting a shadow in between the pages of a double page layout. Currently in SumatraPDF this is a fixed black line in between the page, which does not look very nice in my opinion. The shadow makes it looks like a 'real' book. This is also the case for the other types of books btw. like PDF or EPUB.

Describe the solution you'd like I would love to see an option to either have nothing marking the two pages in the double page layout, the line as it is currently or a shadow like a regular book. Maybe there even could be an option to use your own image?

Describe alternatives you've considered The only thing I can use now it the current method: a black line between the pages.

Additional context See the example screenshot attached.