Examine source code of Massive Migration

{
  "theme": {
    "images": {
      "theme_frame": "MassiveMigration1.jpg"
    },
    "colors": {
      "frame": "#ffffff",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Massive Migration",
  "manifest_version": 2,
  "description": "Named by Denise !  Stop in and visit her StumbleUpon Page !\n<a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/44395e6785d87f967be795699732ea13131a2a3acb506a6ab838ecacf91eb524/http%3A//d55lane.stumbleupon.com/\">http://d55lane.stumbleupon.com/</a>"
}