title: how to reference the Default Recipients set in Jenkins UI
body: <p>I'm using jenkins emailext plugin, in the Jenkins global configuration UI, under <code>Extended E-mail Notification</code> section, I can set <code>Default Recipients</code> to be a list of recipients.</p>
  
  <p>My question is, inside my Jenkinsfile, when I use emailext() step, how can I reference <code>Default Recipients</code> set in the UI, because the <code>to</code> argument for the step only seems to take a String.</p>