Documentation section bloc Extensions for writers is empty about laminas-feed HOT 1 OPEN

/** @var \Zend\Feed\Reader\StandaloneExtensionManager $extensionManager */
$extensionManager = \Zend\Feed\Writer\Writer::getExtensionManager();
$extensionManager->add('My\Entry', \My\Entry::class);
\Zend\Feed\Writer\Writer::registerExtension('My');

var_dump($extensionManager->has('My\Entry')); // true
var_dump(\Zend\Feed\Writer\Writer::getExtensions()['entry']); // array {0 => 'My\Entry'}

$extensionManager->add(\My\Entry::class, \My\Entry::class);
var_dump($extensionManager->has(\My\Entry::class)); // true