This feature is non-standard and is not on a standards track. Do not use it on production sites facing the Web: it will not work for every user. There may also be large incompatibilities between implementations and the behavior may change in the future.


If you're developing privileged code, and would like to create a worker that can use js-ctypes to perform calls to native code, you can do so by using ChromeWorker instead of the standard Worker object. It works exactly like a standard Worker, except that it has access to js-ctypes via a global ctypes object available in the global scope of the worker. Examples of ChromeWorker's using js-ctypes are availabe on Github and are linked to from the See Also section below. To use a postMessage with callback version of ChromeWorker that features promises, see PromiseWorker.

Addons must use absolute URLs to load their workers, and those URLs have to be using a chrome:// or resource:// protocol (file:// is not accepted.) Addons that wish to use file:// URLs must first register a resource replacement path, using code like this:

var fileuri =;'resource').
              setSubstitution('my-cool-addon', fileuri);
  var worker = new Worker('resource://my-cool-addon/worker.js');

More references:

See Also

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 Last updated by: nmve,