Specifying multiple targetOrigin uris in postmessage
<p><a href="https://developer.mozilla.org/en-US/docs/Web/API/Window/postMessage" rel="noreferrer"><code>Window.postMessage()</code></a> has a <code>targetOrigin</code> parameter that can be set to a URI (to ensure the message reaches only a specific url). It can also be set to <code>*</code> of course (not recommended), but is there a way to specify multiple URIs as allowed?</p>

<p>At present I'm simply firing off one <code>postMessage()</code> call for each domain, but this seems a bit hacky to say the least.</p>