16.6. Persisting locale and theme preferences via cookies

The locale selector, theme selector and timezone selector all support persistence of locale and theme preference to a cookie. Simply set the cookie-enabled property in components.xml: 
<theme:theme-selector cookie-enabled="true">
  <theme:available-themes>
    <value>default</value>
    <value>accessible</value>
    <value>printable</value>
  </theme:available-themes>
</theme:theme-selector>

<international:locale-selector cookie-enabled="true"/>