Examine source code of QuickManager: Fantasy for Sleeper

{
  "manifest_version": 3,
  "name": "QuickManager: Fantasy for Sleeper",
  "version": "1.5.4",
  "description": "Manage all your Sleeper fantasy football leagues at once: lineup optimizer, gameday board, waivers, trades, power rankings.",
  "permissions": [
    "storage",
    "unlimitedStorage",
    "webRequest",
    "alarms"
  ],
  "host_permissions": [
    "https://sleeper.com/*",
    "https://*.sleeper.com/*",
    "https://api.sleeper.app/*",
    "https://extensionpay.com/*"
  ],
  "background": {
    "scripts": [
      "ExtPay.js",
      "background.js"
    ]
  },
  "content_scripts": [
    {
      "matches": [
        "https://sleeper.com/*",
        "https://www.sleeper.com/*"
      ],
      "js": [
        "content.js"
      ],
      "run_at": "document_idle"
    },
    {
      "matches": [
        "https://extensionpay.com/*"
      ],
      "js": [
        "ExtPay.js"
      ],
      "run_at": "document_start"
    }
  ],
  "action": {
    "default_title": "Open QuickManager",
    "default_icon": {
      "16": "icons/icon16.png",
      "32": "icons/icon32.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "32": "icons/icon32.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "browser_specific_settings": {
    "gecko": {
      "id": "quickmanager@quickmanager.app",
      "strict_min_version": "140.0",
      "data_collection_permissions": {
        "required": [
          "authenticationInfo"
        ],
        "optional": [
          "personalCommunications"
        ]
      }
    },
    "gecko_android": {
      "strict_min_version": "142.0"
    }
  }
}