Examine source code of RequestSpy

{
  "manifest_version": 2,
  "name": "RequestSpy",
  "version": "1.0",
  "icons": {
    "128": "ativo.png"
  },
  "description": "Bisbilhotar as requisições feita pelo navegador.",
  "permissions": [
    "webRequest",
    "<all_urls>",
    "webNavigation",
    "tabs",
    "management",
    "webRequestBlocking"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": true
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{da5da19a-aae9-4629-b784-69e2400f5b5a}"
    }
  }
}