Just look at the W3C HTML Validator for this site:
validator.w3.org/check?uri=http%3A%2F%2F...e=Inline&group=0

That's the reason that browsers like safari can't render fireboard.

I use Safari with Fireboard all the time without issue. What specific problems are you encountering?

Here is OS-X Safari rendering that address:

Safari on the Mac does'nt render anything when it comes to fireboard.

Anyways, I just liked to guide attention to the errors in the HTML output of this site (and mine too!). I guess, there are a couple of things that could be made better by the developers of this already good component.

Sounds like your Safari install got screwed up some how. I've tested on two different Macs and two Windows Machines (Safari 3.0b XP/Vista) and no problems viewing.

As far as HTML output goes for Joomla forums, I've never been one to really care if sites meet strict validation rules. And Fireboard isn't the only

Joomla/SMF on forums.joomla.org does not validate
Joomla/SMF on joomlahacks.com does not validate
Joomla/PHPbb (Mehdi's Phpbb bridge) www.selwane.com/forum/ does not validate

I agree it would be nice for strict validation, but I think currently developers time is best focused elsewhere.