Examine source code of Tortuga

{
  "theme": {
    "images": {
      "theme_frame": "tortuga.jpg"
    },
    "colors": {
      "frame": "#030000",
      "tab_background_text": "#030000"
    }
  },
  "version": "2.0",
  "name": "Tortuga",
  "manifest_version": 2,
  "description": "Tortu, la misma abreviatura lo dice"
}