Examine source code of zurke.nl V2

{
  "theme": {
    "images": {
      "theme_frame": "header.jpg"
    },
    "colors": {
      "frame": "#3b3b3b",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "zurke.nl V2",
  "manifest_version": 2,
  "description": "<a href=\"https://outgoing.prod.mozaws.net/v1/5d31eb001cc71184905020447c7648f30a3043a74ea0a3989746355fcf894a06/http%3A//www.zurke.nl\" rel=\"nofollow\">www.zurke.nl</a> V2 theme"
}