Examine source code of Mooiesite.nl

{
  "theme": {
    "images": {
      "theme_frame": "header.png"
    },
    "colors": {
      "frame": "#000000",
      "tab_background_text": "#000000"
    }
  },
  "version": "2.0",
  "name": "Mooiesite.nl",
  "manifest_version": 2,
  "description": "<a href=\"https://outgoing.prod.mozaws.net/v1/e596f042670869e05249f0554380758ba97e9f95e3b520d87c2cfb64afea8e1f/http%3A//Mooiesite.nl\" rel=\"nofollow\">Mooiesite.nl</a> Header"
}