<!DOCTYPE HTML> <html> <head> <meta charset="UTF-8"> <script> window.addEventListener("message", function(msg) { parent.postMessage(msg.data, "*"); }); parent.postMessage({ first: "a string", second: ["an", "array"], third: {an: 'object'} }, '*'); </script> </head> <body> <h1>Inner iframe</h1> </body> </html>
