Implementations are missing navigator.serviceWorker in workers

Hi!

I am doing some exploration into Web Workers and Service Workers and the communication mechanism between them.

I was expecting inside DedicatedWorkerGlobalScope -> WorkerNavigator there to be the seviceWorker property for the ServiceWorkerContainer.

// Inside web-worker.js
async function postMessageToServiceWorker() {
    const reg = await self.navigator.serviceWorker.getRegistration(); // <-- throws exception, 'serviceWorker' undefined
    reg.active.postMessage({ some: 'message' });
}

According to the spec, I think this is supposed to be populated? But I haven't found a clear answer one way or another.

Is this just a browser compatibility bug? Is there a clear answer to whether or not the ServiceWorkerContainer is supposed to be available in Web Workers?

I tried testing in Chromium Edge, Chrome, and Firefox latest.

Review the linked ServiceWorker specification and the reported behavior in DedicatedWorkerGlobalScope and WorkerNavigator; reproduce the navigator.serviceWorker lookup in Chromium Edge, Chrome, and Firefox. Done means establishing whether the property is specified and implemented, then recording the compatibility or specification conclusion.