Examine source code of Firefox 6

{
  "theme": {
    "images": {
      "theme_frame": "Firefox6head.jpg"
    },
    "colors": {
      "frame": "#aba8a8",
      "tab_background_text": "#aba8a8"
    }
  },
  "version": "2.0",
  "name": "Firefox 6",
  "manifest_version": 2,
  "description": "Firefox 6 on Hubble photograph background.\nSilver text.\nEnjoy."
}