[S]Doesn't work in Firefox

If I remove the style "Display: none" it works and shows a Box, but a very long Box with Text[/S]
It works now fine. I removed all my old Firefox-Settings and uninstalled Firefox and reinstalled with the new 1.507.
now i figured out in what the problem is. if i anonymize my firefox and i make useragent.override then the ajax-script doesn't work.
I uninstalled it again