Examine source code of TuMetropolis.com

{
  "theme": {
    "images": {
      "theme_frame": "arribafinal.png"
    },
    "colors": {
      "frame": "rgba(229,230,232,1)",
      "tab_background_text": "#000"
    }
  },
  "version": "2.0",
  "name": "TuMetropolis.com",
  "manifest_version": 2,
  "description": "<a href=\"https://outgoing.prod.mozaws.net/v1/53b67b73dfa47d30eae0609a2d2b796c428829de5a1b10a2913f8ec5f29f26a2/http%3A//www.tumetropolis.com\" rel=\"nofollow\">www.tumetropolis.com</a>\ntu metropolis\n<a href=\"https://outgoing.prod.mozaws.net/v1/96fe9e4c225d81b4600d7d94506bee10b6824c6c942a9efc0ff7e13a0ad21e4a/http%3A//tumetropolis.com\" rel=\"nofollow\">tumetropolis.com</a>"
}