Examine source code of TFN Connect for ESPN

{
  "manifest_version": 3,
  "name": "TFN Connect for ESPN",
  "description": "Link your ESPN fantasy leagues to The Fantasy Network in one click — no passwords shared.",
  "version": "1.0.0",
  "icons": {
    "16": "icon-16.png",
    "32": "icon-32.png",
    "48": "icon-48.png",
    "128": "icon-128.png"
  },
  "default_locale": "en",
  "permissions": [
    "cookies",
    "storage"
  ],
  "host_permissions": [
    "*://*.espn.com/*"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "espn-connect@thefantasynetwork.ai",
      "data_collection_permissions": {
        "required": [
          "authenticationInfo"
        ]
      }
    },
    "gecko_android": {}
  },
  "background": {
    "scripts": [
      "background.js"
    ]
  },
  "action": {
    "default_title": "TFN Connect for ESPN",
    "default_popup": "popup.html"
  },
  "content_scripts": [
    {
      "matches": [
        "https://thefantasynetwork.ai/*",
        "https://uat.thefantasynetwork.ai/*"
      ],
      "run_at": "document_start",
      "js": [
        "content-scripts/tfn-bridge.js"
      ]
    }
  ]
}