Examine source code of Notebook

{
  "name": "Notebook",
  "manifest_version": 2,
  "version": "1.0",
  "theme": {
    "images": {
      "theme_frame": "1000181330.jpg"
    },
    "colors": {
      "frame": "rgba(209, 151, 15, 1)",
      "tab_background_text": "rgba(77, 22, 22, 1)"
    }
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{2839352d-4dfd-4be9-925f-3f25bcddb49d}"
    }
  }
}