/**
* Return all markers and their values as associative array
* @param Email $email
* @return string[]
*/
private function getMarkers(Email $email)
{
$markers = $email->getRecipientData();
// Add predefined markers
$markers['newsletter_view_url'] = $email->getViewUrl();
$markers['newsletter_unsubscribe_url'] = $email->getUnsubscribeUrl();
return $markers;
}