Is cross-origin postMessage broken in IE10?

Question

I\'m trying to make a trivial postMessage example work...

• in IE10
• between windows/tabs (vs. iframes)
• across origins

Answer 1

This solution involves adding the site to Internet Explore's Trusted Sites and not in the Local Intranet sites. I tested this solution in Windows 10/IE 11.0.10240.16384, Windows 10/Microsoft Edge 20.10240.16384.0 and Windows 7 SP1/IE 10.0.9200.17148. The page must not be included in the Intranet Zone.

So open Internet Explorer configuration (Tools > Internet Options > Security > Trusted Sites > Sites), and add the page, here I use * to match all the subdomains. Make sure the page isn't listed in the Local intranet sites (Tools > Internet Options > Security > Local Intranet > Sites > Advanced). Restart your browser and test again.

In Windows 10/Microsoft Edge you will find this configuration in Control Panel > Internet Options.

UPDATE

If this doesn't work you could try resetting all your settings in Tools > Internet Options > Advanced Settings > Reset Internet Explorer settings and then Reset: use it with caution! Then you will need to reboot your system. After that add the sites to the Trusted sites.

See in what zone your page is in File > Properties or using right click.

UPDATE

I am in a corporate intranet and sometimes it works and sometimes it doesn't (automatic configuration? I even started to blame the corporate proxy). In the end I used this solution https://stackoverflow.com/a/36630058/2692914.