Examine source code of background for Firefox 4

{
  "theme": {
    "images": {
      "theme_frame": "preview_large2.4.jpg"
    },
    "colors": {
      "frame": "#315cf7",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "background for Firefox 4",
  "manifest_version": 2,
  "description": "is an issue that remains, in my opinion, very well as a background in firefox 4"
}