The Client interface represents an executable context such as a Worker, or a SharedWorker. Window clients are represented by the more-specific WindowClient. You can get Client/WindowClient objects from methods such as Clients.matchAll() and Clients.get().

Client.postMessage()

Sends a message to the client.

Client.frameType Read only

The client's frame type as a string. It can be "auxiliary", "top-level", "nested", or "none".

Client.id Read only

The universally unique identifier of the client as a string.

Client.type Read only

The client's type as a string. It can be "window", "worker", or "sharedworker".

Client.url Read only

The URL of the client as a string.

• Using Service Workers
• Is ServiceWorker ready?
• Promises