title: How to make PrimeNG Dropdown Keyboard Accessible
body: <p>I want to make dropdown keyboard accessible. Right now, its not working when i am using keyboard up and down arrow. I applied tabindex but still not working. Anyone have any idea about this.. </p>
  
  <pre><code>&lt;p-dropdown [options]="cities" tabindex="1" placeholder="Select an option"&gt;&lt;/p-dropdown
  </code></pre>