Payload of the port:message event.
A message reached a port. Each receiving port gets its own event, sent to the window that opened it: port.postMessage reaches every other port on the sender's channel, the sender's own window included, and port.postMessageTo reaches one port.
Payload of the
port:messageevent. A message reached a port. Each receiving port gets its own event, sent to the window that opened it:port.postMessagereaches every other port on the sender's channel, the sender's own window included, andport.postMessageToreaches one port.