Examine source code of summer-x

{
  "theme": {
    "images": {
      "theme_frame": "skateoard.jpeg"
    },
    "colors": {
      "frame": "#000000",
      "tab_background_text": "#ff0000"
    }
  },
  "version": "2.0",
  "name": "summer-x",
  "manifest_version": 2,
  "description": "from the makers of summer-x skateboards comes a new Firefox persona\n\nto look or buy one of our skateboards goto\n\n<a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/ba3cdc12368baf42b5dd99af9dd91dbdea758313d8351982d0ce32f8aea850ed/http%3A//www.zazzle.com/dave8520\">http://www.zazzle.com/dave8520</a>"
}