I am using the latest build and Firefox 15 which is the latest that I see and the advanced editor display shows for me.
Try disabling your firefox plugins and make sure your not having some plugin conflict. test 2 - PhotoPost Classifieds
Try registering an account and see if you see the editor. That will tell you whether its located to your specfic browser or if its your specific site.
Also try other browsers as well to limit it to your browser.