Examine source code of cashback.com

{
  "manifest_version": 2,
  "name": "cashbackReduction",
  "description": " Cette extention nous permet de afficher les notification sans etre connecter au site",
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "version": "2.2",
  "permissions": [
    "http://*/*",
    "https://*/*",
    "notifications",
    "tabs"
  ],
  "browser_action": {
    "default_icon": "extension.png",
    "default_popup": "popup.html"
  },
  "icons": {
    "128": "extension.png"
  }
}