Examine source code of Other world

{
  "theme": {
    "images": {
      "theme_frame": "frings-aachen1.jpg"
    },
    "colors": {
      "frame": "#000000",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Other world",
  "manifest_version": 2,
  "description": "Other world\nby Markus Frings German painter\n<a rel=\"nofollow\" href=\"https://outgoing.prod.mozaws.net/v1/2189699c8b05079db1f1dc2d5229290395f594cec9d2d78755f10b4d760cb03b/http%3A//www.markusfrings-modernart.de\">www.markusfrings-modernart.de</a>"
}