I've got Firefox version 37.0.2, and I can't post anything in Firefox. The only field I can type in is the Title field. Nothing happens to my cursor when I click in the area where I'm supposed to type the post. I also can't see the icons for font size and style, etc. And the post area is white instead of light gray. I had to type this in Internet Explorer!

It looks like there's a version 38 available now, so maybe I will try that...