Examine source code of Mozilla

{
  "theme": {
    "images": {
      "theme_frame": "Mozilla_header.jpg"
    },
    "colors": {
      "frame": "#f7f7f7",
      "tab_background_text": "#f7f7f7"
    }
  },
  "version": "2.0",
  "name": "Mozilla",
  "manifest_version": 2,
  "description": "Mozilla header and footer"
}