Examine source code of CF Live Headers

{
  "name": "CF Live Headers",
  "description": "Displays the live log with the http requests headers",
  "version": "3.7.4",
  "permissions": [
    "debugger"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_action": {
    "default_icon": "icon.png",
    "default_title": "CF Live Headers"
  },
  "manifest_version": 2
}