Color Palette Grayed-out Troubleshooting disables/blocks the Color palette in the Design, when the Advance Customization option is being used, since all the color can be edited by changing the CSS design.

(if you are having problems seeing pictures in this article, click any and they will expand).

However if the Advance Customization is not needed, this can be disabled in order to enable the Color palette with the steps below:
  1. Go to Design
  2. Click on Advance Customization
  3. Then Click on "Discard Changes" button located at the bottom of the CSS column
  4. A pop up message will be displayed to confirm the discard action, Click on "I understand, I'd like to continue" button to confirm
  5. The Color palette option will then be enabled