Examine source code of Validate HTML

{
  "manifest_version": 2,
  "name": "HTML Validator",
  "version": "1.3.4resigned1",
  "description": "Submits HTML source of current tab to the W3C Validator. Not for use on pages that may contain sensitive information.",
  "icons": {
    "72": "icons/checkmark-72.png"
  },
  "browser_action": {
    "default_icon": {
      "72": "icons/checkmark-72.png"
    },
    "default_title": "Validate HTML"
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "permissions": [
    "activeTab"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{69ab40ab-8b3c-4506-9eaa-198b29d8b584}"
    }
  }
}