Flash Player is buggy and always vulnerable to attacks. Lots of website ditching Flash Player and embracing new alternates.
In CF, Flash Player is needed to view the code during hack. You can't copy the code and I think that's the reason to use it.
But wouldn't it be nice, if same functionality could be implemented without the need of Flash Player.
Just a thought. Hope MikeMirzayanov will take this into consideration for this awesome platform.