Examine source code of Extenssr

{
  "manifest_version": 3,
  "name": "Extenssr",
  "version": "4.20.69",
  "description": "Extenssr - A browser extension for Geoguessr",
  "icons": {
    "48": "icons/extenssr_48.png",
    "128": "icons/extenssr_128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.geoguessr.com/*"
      ],
      "js": [
        "src/content.js"
      ],
      "run_at": "document_start"
    }
  ],
  "web_accessible_resources": [
    {
      "resources": [
        "src/injected.js"
      ],
      "matches": [
        "https://www.geoguessr.com/*"
      ]
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{43a33a4b-fced-4774-865e-6b29f13b2724}",
      "data_collection_permissions": {
        "required": [
          "none"
        ]
      }
    }
  }
}