WordPress Media Library Folders + Custom Linux Server Hosting

I figure it out ! Thanks to the wonderful FileBird’s team !

There is the answer :

Add to your function.php file this line of code :

if (defined('NJFB_REST_URL')) {
    add_filter('filebird_json_url', function(){
        return site_url("index.php/wp-json/" . NJFB_REST_URL);
    });

Thank me later ! 😉