Examine source code of Calculator

{
  "manifest_version": 3,
  "name": "QuickCalc",
  "version": "2.0",
  "description": "A sleek, modern calculator extension for your browser, offering a clean interface for all your basic calculations.",
  "action": {
    "default_popup": "popup.html",
    "default_icon": "icon.png"
  },
  "permissions": [],
  "browser_specific_settings": {
    "gecko": {
      "id": "nishchal@quickcalc.com"
    }
  }
}