-#, --progress-bar Make curl display a simple progress bar instead of the more informational standard meter.

-b, --cookie <name=data> Supply cookie with request. If no =, then specifies the cookie file to use (see -c).

-c, --cookie-jar <file name> File to save response cookies to.

my-react-app/package.json add base href folder

{
  "name": "my-react-app",
  "version": "0.1.0",
  "homepage": "myReactApp/", // <= Add the path name where you'll place the react app in your site

The main difference between the two pages is the method of sending messages. Recieving messages is the same in both.

Send messages to iframe using iframeEl.contentWindow.postMessage Recieve messages using window.addEventListener('message')