Examine source code of Connections Categoriser

{
  "manifest_version": 2,
  "name": "Connections Categoriser",
  "version": "0.1.0",
  "description": "Adds a categorisation mode to the NYT Connections game",
  "homepage_url": "https://rd.nz",
  "permissions": [
    "https://www.nytimes.com/games/connections"
  ],
  "content_scripts": [
    {
      "matches": [
        "https://www.nytimes.com/games/connections"
      ],
      "js": [
        "content.js"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{f7529494-e228-42c3-a40d-a8d2d923f7bc}"
    }
  }
}