The fsb_background_link_target filter allows you to modify the behavior of a link that is added to the background image. 

By default this filter returns an empty string, however you can use it to add any valid string that would function in an HTML anchor tag ( <a>)

To find a list of acceptable attributes to add to this filter, please see this document. Note, the href attribute is already added for you in the image's settings.

Example uses of this filter include:

// Open the link in a new window/tab
add_filter( 'fsb_background_link_target', 'fsb_background_link_target' );
function fsb_background_link_target(){
	return 'target="_blank"';

// Tell search engines not to follow the link
add_filter( 'fsb_background_link_target', 'fsb_background_link_nofollow' );
function fsb_background_link_nofollow(){
	return 'rel="nofollow"';