Examine source code of decaller

{
  "theme": {
    "images": {
      "theme_frame": "decall.png"
    },
    "colors": {
      "frame": "#ffffff",
      "tab_background_text": "#ffcc00"
    }
  },
  "version": "2.0",
  "name": "decaller",
  "manifest_version": 2,
  "description": "a well persona of <a href=\"https://outgoing.prod.mozaws.net/v1/a3b24733f9a6606ec5e394a76f4740405a98c562952b7c8d90ea91c7244d7649/http%3A//decaller.com\" rel=\"nofollow\">decaller.com</a> site"
}