Examine source code of abstract_rainbow

{
  "theme": {
    "images": {
      "theme_frame": "abstract_rainbowalto.jpg"
    },
    "colors": {
      "frame": "#c9c9c9",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "abstract_rainbow",
  "manifest_version": 2,
  "description": "spectrum,purple,violet,blue,turquoise,green,yellow,orange,red,colorful,\nlight,bright,prism"
}