Copy whole Color Palete from reference image inserted on a separate layer

[Option33]

is there a way?

[spookster]

Go to the palette Tab and when you click the configuration cog you can pick "Populate from Document".
Adjust how many colors you want and click Ok.

If you only want the colors from the reference image, you could import the reference image in an empty project.
Use "Populate from Document".
This palette can be saved and loaded in to your other document.