Examine source code of Google WebSearch Only

{
  "manifest_version": 2,
  "name": "Google WebSearch Only",
  "version": "1.2",
  "description": "Add google search that automatically use 'websearch'.",
  "permissions": [
    "storage",
    "webRequest",
    "webRequestBlocking",
    "https://www.google.com/"
  ],
  "browser_specific_settings": {
    "gecko": {
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      },
      "id": "{4ea86f8c-5e9b-4415-a0f8-f689024bfef9}"
    }
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "options_ui": {
    "page": "options.html"
  },
  "browser_action": {
    "default_popup": "options.html"
  }
}