$hub_mode = trim($_GET['hub_mode'] ?? '');
$hub_topic = trim($_GET['hub_topic'] ?? '');
$hub_challenge = trim($_GET['hub_challenge'] ?? '');
$hub_mode = trim($_GET['hub_mode'] ?? '');
$hub_topic = trim($_GET['hub_topic'] ?? '');
$hub_challenge = trim($_GET['hub_challenge'] ?? '');