Examine source code of Happy Easter Egg

{
  "theme": {
    "images": {
      "theme_frame": "EasterHeader1.jpg"
    },
    "colors": {
      "frame": "#b3b3b3",
      "tab_background_text": "#d4d4d4"
    }
  },
  "version": "2.0",
  "name": "Happy Easter Egg",
  "manifest_version": 2,
  "description": "Happy Easter to you all.\n\n<a href=\"https://outgoing.prod.mozaws.net/v1/3955a16d226f18422eeef0cdfa267d8a719f7e3193de679d3120c36447070653/http%3A//www.leighpurtill.com/\" rel=\"nofollow\">http://www.leighpurtill.com/</a>"
}