Examine source code of Mortgage Calculator

{
  "manifest_version": 3,
  "name": "Mortgage Calculator",
  "version": "1.0",
  "description": "A comprehensive mortgage calculator with detailed payment breakdowns and amortization schedule",
  "browser_specific_settings": {
    "gecko": {
      "id": "mortgage-calculator@example.com"
    }
  },
  "action": {
    "default_popup": "popup.html",
    "default_icon": {
      "16": "icons/icon16.png",
      "48": "icons/icon48.png",
      "128": "icons/icon128.png"
    }
  },
  "icons": {
    "16": "icons/icon16.png",
    "48": "icons/icon48.png",
    "128": "icons/icon128.png"
  },
  "permissions": []
}