For testing semi-transparent aliased pixels. Seems there is a cairo bug producing false hsl values at low alpha values. Solid fill, fading gradients, lowered opacity, lowered alpha channel, masking, clipping, compositing by filtering is presented in the image.
transparency test 2 free icon was designed by Lazur URH for icons Png and presented to its users.
Lazur URH
3/24/2018