Examine source code of Rocktrip

{
  "theme": {
    "images": {
      "theme_frame": "Firefoxtop7.jpg"
    },
    "colors": {
      "frame": "#f7ff00",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Rocktrip",
  "manifest_version": 2,
  "description": "This is a official Theme of the Band Rocktrip"
}