Examine source code of Sparrow Flight ver.Orange

{
  "theme": {
    "images": {
      "theme_frame": "sparrowflight3.jpg"
    },
    "colors": {
      "frame": "#a16100",
      "tab_background_text": "#3d0000"
    }
  },
  "version": "2.0",
  "name": "Sparrow Flight ver.Orange",
  "manifest_version": 2,
  "description": "A sparrow flies across your browser over a warm orange-brown background. Art by Kate N.Y."
}