Examine source code of DNS lookup - HTTP status

{
  "manifest_version": 2,
  "name": "DNS lookup - HTTP status",
  "browser_action": {
    "default_icon": "icon.png"
  },
  "description": "Analyze domain dns zone and http status",
  "version": "1.2resigned1",
  "permissions": [
    "tabs"
  ],
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{57e29077-b75e-48ac-9d76-f777709ef265}"
    }
  }
}