Examine source code of new colors test

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#665858",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "new colors test",
  "manifest_version": 2,
  "description": "nice effect with the add-on Stratiform by inverting the colors of the top and of the tabs"
}