Create a transport for code running inside an iframe.
The child repeatedly offers a MessagePort to its parent until the matching
acknowledgement arrives. Calls made before readiness are queued; closing
clears retries and closes candidate or ready ports.
Create a transport for code running inside an iframe.
The child repeatedly offers a
MessagePortto its parent until the matching acknowledgement arrives. Calls made before readiness are queued; closing clears retries and closes candidate or ready ports.