Examine source code of Dumperfoo.com

{
  "theme": {
    "images": {
      "theme_frame": "dumperfoo_persona_header.png"
    },
    "colors": {
      "frame": "#ff0000",
      "tab_background_text": "#ffffff"
    }
  },
  "version": "2.0",
  "name": "Dumperfoo.com",
  "manifest_version": 2,
  "description": "Branded persona to match <a href=\"https://outgoing.prod.mozaws.net/v1/fc2d405289fcb06522ab4eefe6e671104f2469ee986942bf9522edda996f52ef/http%3A//dumperfoo.com\" rel=\"nofollow\">dumperfoo.com</a>"
}