Examine source code of MusicGround

{
  "theme": {
    "images": {
      "theme_frame": "MG.jpg"
    },
    "colors": {
      "frame": "#000000",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "MusicGround",
  "manifest_version": 2,
  "description": "the best of dark music <a href=\"https://outgoing.prod.mozaws.net/v1/9fb7200db3cb61ba804a2edc645677b1bb0fec0f9a7744a6641b2dde6525f967/http%3A//ww.musicground.com.br\" rel=\"nofollow\">ww.musicground.com.br</a> or <a href=\"https://outgoing.prod.mozaws.net/v1/c012abb0c3cc76db47666e628d2df1235ed6ce82c36ad92bccfe99618021977f/http%3A//ww.gothicground.com\" rel=\"nofollow\">ww.gothicground.com</a>"
}