NO_SCALE problems

I am trying to make my movie 100%X100% and not scale on browser resize. I am using:

stage.scaleMode = StageScaleMode.NO_SCALE;

It works great in the flashplayer, but when I try it firefox. I get:

TypeError: Error #1009: Cannot access a property or method of a null object reference.
at main_fla::MainTimeline/frame1()

Did a lil research on #1009:

1009 %s ‘%s’ has no type declaration.

Not declaring a data type is a coding style preference. A function return type, parameter, or variable has no type declaration. However, using type declarations enables the compiler to write more efficient code, as well as detect more errors at compile time. Enable this warning if you want to be reminded when you fail to use a type declaration.

How hard can this be? AS3 is a bummer. I really want to get in to it. But it seem much more complicated.

Thanks :thumb2: