Examine source code of Classy Ubuntu

{
  "theme": {
    "images": {
      "theme_frame": "headubuntu.jpg"
    },
    "colors": {
      "frame": "#808080",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Classy Ubuntu",
  "manifest_version": 2,
  "description": "A slick looking Ubuntu persona. Took me 2 hours, I even created a super resolution Ubuntu logo just for this!"
}