Color picker: how to pick a color with transparency

[ashf]

Is it possible to pick a color with transparency value together?

[Alfred]

I don’t think it is possible, but it should be! The software obviously knows whether a pixel which looks pink on a white background is actually red with reduced opacity.

[ashf]

I see, so there isn't such a feature now.
I think switching picking mode with a modifier key might be convenient.
(switching between display color and raw color with transparency)