FacetWP – set ACF relationship facet value to the post’s slug instead of ID

<?php

add_filter( 'facetwp_index_row', function( $params, $class ) {
    if ( 'job_company' == $params['facet_name'] ) {
        if ( ! empty( $params['facet_value'] ) ) {
            $post = get_post( (int) $params['facet_value'] );
            $params['facet_value'] = $post->post_name;
        }
    }
    return $params;
}, 10, 2 );