Examine source code of Vanilla Twilight

{
  "theme": {
    "images": {
      "theme_frame": "vanillatwilightfirefoxpersonahead.JPG"
    },
    "colors": {
      "frame": "#97b851",
      "tab_background_text": "#7fe02a"
    }
  },
  "version": "2.0",
  "name": "Vanilla Twilight",
  "manifest_version": 2,
  "description": "owl city - vanilla twilight"
}