background color HTMLLoader

hi,

I'm using HTMLLoader to load a webpage and I'd like to change the background color of the HTMLLoader.

From the docs I understand that if I set paintsDefaultBackground to false and apply a color value to opaqueBackground,

the HTMLLoader should have that backgroundcolor. And setting opaqueBackground to null should make it transparent.

But I keep seeing the opaque white default bg color of the HTMLLoader. My code:

_html = new HTMLLoader();

  //should show transparent html loader but doesn't work

                              _html.paintsDefaultBackground = false;

                              _html.opaqueBackground = null;

   _html.width = stage.stageWidth;

  _html.height = stage.stageHeight;

                              addChild(_html);

                              _html.load(new URLRequest("bla.com));

Any ideas would be very welcome!

thanks,

Jeff.