Examine source code of Automatic Unit Converter

{
  "manifest_version": 2,
  "name": "Automatic Unit Converter",
  "version": "1.4resigned1",
  "description": "Automatically different (American) units to their SI/Europian counterparts.",
  "permissions": [
    "storage"
  ],
  "icons": {
    "48": "icons/border-48.png"
  },
  "content_scripts": [
    {
      "matches": [
        "<all_urls>"
      ],
      "js": [
        "background.js"
      ]
    }
  ],
  "options_ui": {
    "page": "options.html"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "{47a3bbae-80f8-4098-97ff-4a27d98c10bd}"
    }
  }
}