I am not really sure what the test plan means when it says the blended element should have a transparent "background-color". In CSS, 'transparent' is a color keyword, meaning RGBA(0, 0, 0, 0). It is the default element background color.

The original test seems to have no background-color for the blender element.

I am not sure if the test plan means to say that the blended element should have a color with 'alpha != 1'