Cool?
Symantec build script blockers into their products wasting resources watching programs like media player, which have no reason to run scripts, causing all sorts of problems if something goes wrong with symantec sblock. Services.msc uses activex too untill you hit standard view. Why??. And security controls in gpedit.msc that actually prevent you from activating Windows but hardly cause any other problems.

I'm guessing mozilla have good reason* and running perl client side is not prevalent enough, to force their hand, like javascript, but it can be enabled with addons.

* Known good Scripts need to run from read only sources and externally sourced code cannot be known good and so needs an architecture to hopefully protect the user, better than Java has and especially activeX.