There's a reason I won't download this Rated 1 out of 5 stars

I won't download this update because it modifies the web page.As a web developer I can't install anything like that because it will affect the apperance of clients' designs and that is unacceptable. I don't want to switch profiles to do this. If would be nicer if you could toggle it on / off but I doubt there's any way to do this, please correct me if I'm wrong.