Examine source code of TshirtMonster_1

{
  "theme": {
    "images": {
      "theme_frame": "TSM_persona_head.jpg"
    },
    "colors": {
      "frame": "#ffffff",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "TshirtMonster_1",
  "manifest_version": 2,
  "description": "Create custom t-shirts, make personalized t-shirts, sell your custom t-shirt designs at <a href=\"https://outgoing.prod.mozaws.net/v1/adee6651aec19ba9052f2b9023757f1598f1632c9d95e73cd0590c0182350586/http%3A//T-Shirtmonster.ca\" rel=\"nofollow\">T-Shirtmonster.ca</a>, your custom t-shirt printer. Open a free gallery and upload your own artwork to sell! Get Creative!"
}