Examine source code of Search Position Marker

{
  "manifest_version": 2,
  "name": "Search Position Marker",
  "version": "1.0",
  "description": "Enhance your DuckDuckGo experience by placing a marker next to links that also appear in Google search results. Easily identify overlap and compare rankings seamlessly",
  "content_scripts": [
    {
      "matches": [
        "*://*.google.com/search?*"
      ],
      "js": [
        "ddgposition.js"
      ]
    }
  ],
  "permissions": [
    "*://html.duckduckgo.com/html/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{72ab0f59-9f00-4212-8873-9ddc1f6436db}"
    }
  }
}