Color picker not working in OSX?

I am trying to pick colors (backgrounds, Hue Curves, anywhere with color) by holding down on the Pick button so that the cursor changes to the eyedropper, then dragging over the image.

All tutorials indicate that I should see an overlay with the RGBA values and that when I release the button, the color will be picked up. This doesn't happen. Nothing happens except a one-pixel white dot appears some distance from the cursor which tracks cursor movement but doesn't seem to do anything.

Any help?

OSX 10.11.4, Fusion 8

For me color picker works fine for 1 pixel but i couldn't activate area selection by pressing option key neither with tablet nor with mouse...

Color picker Doesn't work properly if the resolution of the screen is set to something above 1080p and the user interface is set to scale 200% or auto, only works with 100% scale and also in 3D viewer on the left can't click to select the camera for the same reason, works only if scale is set to 100% this behavior is on windows.

Color picker Doesn't work properly if the resolution of the screen is set to something above 1080p and the user interface is set to scale 200% or auto, only works with 100% scale and also in 3D viewer on the left can't click to select the camera for the same reason, works only if scale is set to 100% this behavior is on windows.

This still seems to be an issue today? Can't manage to make it work with a 4k screen at 125% scaling even though the app itself doesn't scale anyway