Always show next / prev links in pager

<?php
/** shows prev link while on page 1 and next link while on last page
 **/
add_filter( 'facetwp_facet_html', function( $output, $params ) {
    if ( 'standard_pager' == $params['facet']['name'] ) { // change 'standard_pager' to name of your pager facet
        $page = FWP()->facet->pager_args['page'];
        $total = FWP()->facet->pager_args['total_pages'];
        if ( 2 > $page ) { // if this is page 1
            // add the prev page link
            $label = facetwp_i18n( $params['facet']['prev_label'] );
            $class = 'facetwp-page prev active';
            $data = ' data-page="1"';
            $html = '<a class="' . $class . '"' . $data . '>' . $label . '</a>';
            $output = str_replace( '<div class="facetwp-pager">', '<div class="facetwp-pager">' . $html, $output );           
        } elseif ( $page == $total) { // if this is last page
            // add the next page link
            $label = facetwp_i18n( $params['facet']['next_label'] );
            $class = 'facetwp-page next active';
            $data = ' data-page="' . $page .'"';
            $html = '<a class="' . $class . '"' . $data . '>' . $label . '</a>';
            $output = str_replace( '</div>', $html . '</div>', $output ); // 
        }
    }
    return $output;
}, 10, 2 );