Examine source code of eSave

{
  "name": "eSave",
  "manifest_version": 2,
  "version": "5.0.1",
  "description": "Descontos aplicados automaticamente quando você faz compras online!",
  "applications": {
    "gecko": {
      "id": "jid0-rvBmQxOljnOWENsneygXyoLMv9U@jetpack"
    }
  },
  "background": {
    "scripts": [
      "js/jquery-3.2.0.min.js",
      "settings.js",
      "background.js"
    ],
    "persistent": false
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "js/jquery-3.2.0.min.js",
        "content.js"
      ]
    }
  ],
  "browser_action": {
    "default_icon": "icon.png"
  },
  "icons": {
    "128": "128.png"
  },
  "permissions": [
    "storage",
    "https://d34q2t9522j8qp.cloudfront.net/*"
  ]
}