Examine source code of Dusseldorf

{
  "theme": {
    "images": {
      "theme_frame": "dues1.jpg"
    },
    "colors": {
      "frame": "#cbcccf",
      "tab_background_text": "#adb5c2"
    }
  },
  "version": "2.0",
  "name": "Dusseldorf",
  "manifest_version": 2,
  "description": "Düsseldorf in der nacht."
}