Can't access drawing functions from FF on ArchLinux

Reported by a user. Unverified by me, as I don't have a Linux machine on me.

"I'm running Arch Linux with Firefox 36.0.1 and I can't access the drawing functions from object methods. For example, if I define a rectangle constructor and draw function:

var Rectangle = function(x1, y1, x2, y2) {
...
};
Rectangle.prototype.draw = function() {
fill(this.color);
rect(this.x1, this.y1, this.w, this.h);
};

I will get errors because 'fill' isn't defined. I've confirmed that this doesn't happen on Chromium 41.0.2272.76 on the same Arch Linux system."

Reproduce the reported Rectangle example in Firefox 36.0.1 on Arch Linux and compare it with Chromium 41.0.2272.76. Trace how drawing functions such as fill and rect are exposed inside object methods; the issue is done when the behavior is understood and the reported example works consistently or the incompatibility is clearly documented.

Written by the indexing model from the issue text.