The fsb_random_image_no_slideshow filter changes the functionality of the plugin when multiple images are assigned to the same page.

By default the filter returns false, which maintains the plugin's original functionality.

Returning true will enable a random image to be displayed. The following code can go in your theme's functions.php file or in a custom plugin.

add_filter( 'fsb_random_image_no_slideshow', '__return_true' );

An array of $ids is also passed to the filter, which represents an array of the id number(s) of the images that are being displayed as found in the table on Appearance > Fullscreen BG Image. These ids allow you to only display a random image if certain images are displayed. For example, you want a random image displayed on your shop page, and have images 1, 2, and 3 assigned to the shop page. You can use the function you use to process this filter to check if images 1, 2, and/or 3 are in the array of $ids before returning true.

add_filter( 'fsb_random_image_no_slideshow', 'my_custom_function' );
function my_custom_function( $ids ){
	if( in_array( 1, $ids ) && in_array( 2, $ids ) && in_array( 3, $ids ) ){
		return true;
	} else {
		return false;