Hmm, yeah FF is a bit wonky. At least, I see the offset + on the greentooth "awesome" button. But the sign-in page looks normal to me. Firefox 48.0.2 on Windows 8.1.
When replying, sometimes texts are not bold in the editor but when I click "post reply" the texts are shown as expected. Also sometimes here are lots of line spaces in the editor. I'm using FF latest version.