Image Widget Plus - Randomize order of all Slideshows

functions.php

<?php

/**
 * Image Widget Plus - Randomize order of all Slideshows
 *
 * From https://gist.github.com/cliffordp/7b1d298baf55121ec3a54e63b5f8b009
 * For https://theeventscalendar.com/support/forums/topic/image-widget-pro-slideshow-and-random/
 *
 * @link https://theeventscalendar.com/product/wordpress-image-widget-plus/
 *
 * @see  Tribe__Image__Plus__Widget::widget()
 */
add_filter( 'tribe_image_plus_widget_instance', 'cliff_image_widget_plus_randomize_slideshow' );
function cliff_image_widget_plus_randomize_slideshow( $instance ) {
	// only if we are in a Slideshow type of IW+ widget
	if ( 'slideshow' === $instance['display'] ) {
		shuffle( $instance['attachments'] );
	}

	return $instance;
}