Press Enter to sample the color; don't click.
It would be nice if clicking worked for this. It does in Cinema 4D. I'll file a feature request.
That's what I thought.
That tip doesn't seem to work with the Chrome Palette Pocket extension: Color Palette Pocket - Chrome Web Store
EDIT: Eyedropper wasn't working yesterday. Now it's working today. Weird.
Glad it's working.