Hi all,
I am presently experimenting with different color temperatures, and I just discovered this peculiarity.
Here is the image, just opened in darktable 3.0.0rc1+28:

These are the RGB values according to the color picker:

… and the corresponding Lab values:

Why values outside of RGB 0 – 255 [R has a value of -191 for the green swatch, for instance]? Is there something that I have missed?
Have fun!
Claes in Lund, Sweden