WhatsApp Embedded Signup

This page starts Meta Embedded Signup and listens for WA_EMBEDDED_SIGNUP session info through browser postMessage.

Start signup flow

Configuration ID

App ID

This uses the Embedded Signup code setup generated by Meta for this app.

Pre-filled form data JSON

Waiting for signup session events.

Latest session info

No session info received yet.

Backend handoff

When Facebook Login returns a code, this page sends the code plus the latest WABA/Phone session info to the backend for server-side token exchange.

No auth code received yet.

Exchange Token

Paste the App Secret here after Embedded Signup finishes. The exchange runs server-side without a redirect URI, and the token is saved outside public_html.

App Secret

Authorization code

No token exchange attempted yet.

What this page listens for

window.addEventListener('message', (event) => {
  if (event.origin !== 'https://www.facebook.com') return;
  const data = JSON.parse(event.data);
  if (data.type === 'WA_EMBEDDED_SIGNUP') {
    // session info is available here
  }
});