Examine source code of xxstension

{
  "manifest_version": 2,
  "name": "Haxxor Payloads",
  "version": "1.0",
  "description": "Store your xss payload and get it in your clipboard by cliking ont it",
  "icons": {
    "32": "icons/nuclear.png"
  },
  "permissions": [
    "activeTab",
    "storage"
  ],
  "browser_action": {
    "default_icon": "icons/nuclear.png",
    "default_title": "XXSTension",
    "default_popup": "popup/main.html"
  },
  "applications": {
    "gecko": {
      "id": "xsstension@xxstension.com"
    }
  }
}