Examine source code of Currency Converter

{
  "manifest_version": 2,
  "name": "Currency Converter",
  "version": "1.0",
  "description": "Convert currencies in real time.",
  "icons": {
    "64": "icon64.png",
    "128": "icon128.png"
  },
  "browser_action": {
    "default_popup": "popup.html",
    "default_icon": {
      "64": "icon64.png",
      "128": "icon128.png"
    }
  },
  "permissions": [
    "https://api.exchangerate-api.com/"
  ],
  "browser_specific_settings": {
    "gecko": {
      "id": "{b9f9a30b-e642-4117-86f7-0cbfd5ab1642}",
      "strict_min_version": "102.0"
    }
  }
}