Examine source code of Backstabbr Names

{
  "manifest_version": 2,
  "name": "Backstabbr Names",
  "version": "1.1.0",
  "description": "A browser extension to add user names to the Backstabbr web app.",
  "icons": {
    "48": "public/icon-48.png",
    "128": "public/icon-128.png"
  },
  "content_scripts": [
    {
      "matches": [
        "https://www.backstabbr.com/game/*"
      ],
      "js": [
        "content/index.js"
      ],
      "run_at": "document_end"
    }
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{09548763-6edd-456b-9c38-128477408082}"
    }
  }
}