An optional PostMessageOptions object is being added to the postMessage() function for 6 of the 7 interfaces where it’s supported, specifically, DedicatedWorkerGlobalScope, Worker, ServiceWorker, ServiceWorker, and Window. This gives the function a similar interface on its definitions and allows it to be extended in the future. Since broadcastChannel.postMessage() doesn't take additional arguments (such as transfer) it is not being changed.




Specification link

Specification currently under development in a Working Group

Status in Chromium


Enabled by default (tracking bug)

Consensus & Standardization

After a feature ships in Chrome, the values listed here are not guaranteed to be up to date.


Last updated on 2021-12-21