Examine source code of FireFox Beta

{
  "theme": {
    "images": {
      "theme_frame": "firefox-lowresver-banner-lower.jpg"
    },
    "colors": {
      "frame": "#003ba1",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "FireFox Beta",
  "manifest_version": 2,
  "description": "Simple FireFox banner theme, combined with a picture by someone I follow on DeviantArt."
}