facetwp pre-select from ACF field

<?php
/**
 * Pre-select facet choices in FacetWP.
 */
add_filter( 'facetwp_preload_url_vars', function( $url_vars ) {
	$page = get_page_by_path( FWP()->helper->get_uri() ); // for "page" post type, other post types may need different checks
	$value = get_field( 'somefield', $page->ID );
	if ( !empty( $value ) ) {
		if ( empty( $url_vars['somefacet'] ) ) {
			$url_vars['somefacet'] = array( $value );
		}
	}
	return $url_vars;
} );