I don't know why people are so scared of the registry. I've been editing it constantly within the past two weeks on two computers, it's almost like editing basic files on your computer.
I mean if it's for something like basic window functions, then yeah, you may disable even logging in or something.
But if it has to do with a browser then who cares? If anything does go wrong can't you just uninstall then reinstall? Or go back and re-edit the relevant keys? I don't see why it's so risky.