Examine source code of Drum player

{
  "theme": {
    "images": {
      "theme_frame": "Lassetrommeheader.jpg"
    },
    "colors": {
      "frame": "#fff7f7",
      "tab_background_text": "#fa7373"
    }
  },
  "version": "2.0",
  "name": "Drum player",
  "manifest_version": 2,
  "description": "This is me at a concert. Picture taken by a friend."
}