In each preview session, the browser displays the following controls:
As User is a drop down menu of preview profiles. Use this menu to change the user profile. Then click Preview Landing Page to refresh the page with the new profile.
Changing user profiles during a given session has no effect on the settings that are used when you launch a new session.
Preview Landing Page refreshes the browser window with the original preview URL.
Remove Frame removes the frame from the pages in the current session.