Examine source code of Firefox rules

{
  "theme": {
    "images": {
      "theme_frame": "firefoxcopie.jpg"
    },
    "colors": {
      "frame": "#c90000",
      "tab_background_text": "#787777"
    }
  },
  "version": "2.0",
  "name": "Firefox rules",
  "manifest_version": 2,
  "description": "a little test!"
}