Please see forum post: http://flowplayer.org/tools/forum/35/77798
History causes issues in both browsers when used:
history: true in the DOM call messes it up so that the tabs don't work. The previous and next functions work fine however, just not with the browser back/forward.
Fixed in dev, looks like newer firefox now has a hard requirement on the 2nd param to pushState, which was previously omitted.