Examine source code of Google NCR

{
  "manifest_version": 2,
  "name": "Google NCR",
  "description": "Change Google region + disable personalized web search + safe search off",
  "version": "1.0.0",
  "applications": {
    "gecko": {
      "strict_min_version": "57.0"
    }
  },
  "permissions": [
    "search",
    "storage",
    "webRequest",
    "webRequestBlocking",
    "https://*.google.com/*"
  ],
  "chrome_settings_overrides": {
    "search_provider": {
      "name": "Google NCR",
      "search_url": "https://www.google.com/search?q={searchTerms}&pws=0&gl=us&gws_rd=cr&safe=off",
      "favicon_url": "https://www.google.com/favicon.ico",
      "is_default": true
    }
  },
  "content_scripts": [
    {
      "matches": [
        "https://*.google.com/*"
      ],
      "run_at": "document_end"
    }
  ]
}