Examine source code of nightwish group

{
  "theme": {
    "images": {
      "theme_frame": "haut.jpg"
    },
    "colors": {
      "frame": "#1f1e1e",
      "tab_background_text": "#1f1e1e"
    }
  },
  "version": "2.0",
  "name": "nightwish group",
  "manifest_version": 2
}