Examine source code of DuckDuckGo Focus

{
  "manifest_version": 2,
  "name": "DuckDuckGo Focus",
  "version": "1.0",
  "description": "Cleanup the interface from unwanted content such as ads.",
  "icons": {
    "48": "images/duckduckgo-focus.48.png",
    "512": "images/duckduckgo-focus.png"
  },
  "content_scripts": [
    {
      "matches": [
        "*://*.duckduckgo.com/*"
      ],
      "js": [
        "ddg-focus.js"
      ]
    }
  ]
}