SharedWorker: port property
  The port property of the SharedWorker
  interface returns a MessagePort object used to communicate and control
  the shared worker.
Value
A MessagePort object.
Examples
  The following code snippet shows creation of a SharedWorker object using
  the SharedWorker() constructor. Multiple
  scripts can then access the worker through a MessagePort object accessed
  using the SharedWorker.port property — the port is started using its
  start() method:
js
const myWorker = new SharedWorker("worker.js");
myWorker.port.start();
For a full example, see our Basic shared worker example (run shared worker.)
Specifications
| Specification | 
|---|
| HTML Standard  # dom-sharedworker-port-dev  | 
Browser compatibility
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