Light color palette not showing up

I am unable to see the light color palette so that I can copy and edit it although I have set it as my default (same problem when it is not default).
Is there something I am doing wrong here?

If you click on the + New button in your screenshot you’ll get something like this.

create color palette modal

You can then select a base for your new palette. If you select Light, you’ll get a new color palette with the same colors used in the light palette.

From there, you can edit any or all the colors. Once you’re done, give your palette a name and save it. Then head to your theme and set it to the newly created palette.