Examine source code of Yosemite Vista

{
  "theme": {
    "images": {
      "theme_frame": "Yosemite_Header.jpg"
    },
    "colors": {
      "frame": "#454343",
      "tab_background_text": "#fffcfc"
    }
  },
  "version": "2.0",
  "name": "Yosemite Vista",
  "manifest_version": 2,
  "description": "I took this picture at the tunnel into Yosemite.  One of my favorites. \nEnjoy\nsksisme"
}