Comment # 7 on bug 1205774 from Stefan Dirsch

(In reply to Bruno Friedmann from comment #6)
> To Stefan, really strange, since yesterday I've remove the cmdline parameter 
> simplefb=1

simplefb=1 ? It should be nosimplefb=1 !

> 
> and I simply didn't experiment crash, kernel freeze, firefox code error, and
> both external screen can work.
> 
> Maybe that parameter is no more needed?

Could you doublecheck what option you had set?