Examine source code of GFX Heaven

{
  "theme": {
    "images": {
      "theme_frame": "header.jpg"
    },
    "colors": {
      "frame": "#cccccc",
      "tab_background_text": "#ccffff"
    }
  },
  "version": "2.0",
  "name": "GFX Heaven",
  "manifest_version": 2,
  "description": "theme created for <a href=\"https://outgoing.prod.mozaws.net/v1/cd7105d82d6bdbe4673169bc33a247a2cd763a3e734ca77e143055c910f2dd26/http%3A//www.gfxheaven.net\" rel=\"nofollow\">www.gfxheaven.net</a> !"
}