One of the drawbacks in early versions of Lightroom was the inability to click and pick colors from an image for design elements such as strokes and borders. Now it’s really easy. Simply click and drag the eyedropper out of the color picker and onto the image. As you do, the selected color on the color picker updates with the color under the cursor. In the example below you can see where I opened the Stroke Border color picker in Lightroom’s Print module and then dragged the eyedropper out of the color picker to one of the stones to sample its color, which is reflected in the narrow stroke around the image.