We found the bug and fixed it. There should be an update soon. If you'd like fix it now, you can do this.

Follow the instructions on this page to create a userChrome.css file:

http://www.mozilla.org/unix/customizi...

Then add the following to that file:

#main-window[btBoom="lookingforgroup"] statusbarpanel#statusbar-display {
-moz-appearance: none !important;
border: none;
}

Hope that helps!