Examine source code of Currency ConverterX

{
  "manifest_version": 2,
  "name": "Currency Converter",
  "version": "1.0",
  "description": "Converts currency from one Currency TO other Currency",
  "permissions": [
    "https://v6.exchangerate-api.com/*"
  ],
  "background": {
    "scripts": [
      "background.js"
    ],
    "persistent": false
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {}
  },
  "icons": {},
  "browser_specific_settings": {
    "gecko": {
      "id": "{ff8d5ee8-6a07-4e78-b73a-6831022935a1}"
    }
  }
}