Try to use Classic Theme Restorer. It will bring back statusbar, and McAfee Siteadvisor icon on it. https://addons.mozilla.org/en-US/firefox/addon/classicthemerestorer/

Thanks for your reply.

Do you know if there is a screen shot showing the browser with this add on?

If I try this Classic Theme Restorer and don't like it, how do I remove it?

I am using this add-on. On the bottom right corner on the status bar is visible the McAfee Siteadvisor add-on icon. It's not the familiar McAfee subtitle, just a small green like. With the built-in add-on manager you can easy remove the Siteadvisor , if you do not like use it.