Override the expand / collapse icons

functions.php

<?php

add_filter( 'facetwp_assets', function( $assets ) {
    FWP()->display->json['expand'] = '<span>expand</span>';
    FWP()->display->json['collapse'] = '<span>collapse</span>';

    // Return the same thing (since we're hijacking this hook)
    return $assets;
});

Hi
when I used this filter, it prints the whole thing like "< span >expand< /span >", is there anyway we can skip this?

Thank you