Showing option when page is frontpage

Try if ( 'page' == get_option( 'show_on_front' ) ) {}.

Edit

but I’ve tried adding and replacing <?php endwhile; endif; elseif (is_home()): ?> with both of your code. Could you perhaps include your snippet with mine?

I’m not sure why you would do that. I was specifically answering this question:

But what if a page (instead of the ‘blog’) is the frontpage? If possible I’d like to include the option as well.

The answer to that question is what I posted:

`if ( 'page' == get_option( 'show_on_front' )

However, that won’t actually solve your problem, if I’m reading your code properly. Reading what you’re asking, this should work:

if ( is_single() || is_page() || is_front_page() )

(Note: I used || instead of OR as the Boolean operator.)

To be honest, I’m somewhat surprised that this works on static pages. I didn’t know that they generated RSS output.