How do you reliably resize Unity Web Player in Firefox?

I've tried resizing in various ways with both css and javascript. I can get it to work fine in Chrome and Safari, but Firefox plays up. It seem like the player itself is sizing correctly, but the bottom of the player seems to be tied to place that was the bottom when it was first loaded, and when expanding sideways, even though the player expands, it only displays up to the width that it was originally, like you are seeing a "window" into an expanded player.

I notice this even happens with Mars Explorer at dat.mrsxplr.com/play which used to be held up as the guys that had done resizing correctly.

Has anyone got resizing working reliably in Firefox?