Examine source code of TWiT.TV

{
  "theme": {
    "images": {
      "theme_frame": "TWiT-Header.jpg"
    },
    "colors": {
      "frame": "rgba(229,230,232,1)",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "TWiT.TV",
  "manifest_version": 2,
  "description": "This persona if for fans of <a href=\"https://outgoing.prod.mozaws.net/v1/ed6fda6215f1bed7fa2784e2155727c7ac5337bc7b21d3de305d872e77b1b177/http%3A//twit.tv\" rel=\"nofollow\">http://twit.tv</a>"
}