Communicating between a native app and MS Edge or IE in Enhanced Protected Mode?

Question

Is there any plan to allow Edge and EPM IE to communicate over loopback, or some other way for a webapp to communicate with a native app?

I'm working on a product where we would like a webapp to be able to communicate with a native app running on the same machine. We currently have a mechanism where the native app runs a webserver listening on loopback and the webapp makes CORS requests to this webserver. This mechanism works in most browsers except for EPM IE and Edge, where loopback communication is disabled (see "Loopback-blocked" in this MSDN post).

The answer to this SO post suggested that there might be changes to this, but it sounded like that would only be for development/debugging, not for production. It would be great if someone could confirm that.

Related to this, Chromium announced similar plans to block loopback/local network access in the bug Block sub-resource loads from the web to private networks and localhost. However, there seemed to be quite an outcry and it sounded like they wouldn't implement a change without having a replacement mechanism in place.

Ideally we'd prefer a solution that didn't require proxying through our server because of the extra latency and complexity that would introduce.

Answer 1

The FAQ at http://dev.modern.ie/platform/faq/how-can-i-debug-localhost/ changed recently:

Microsoft Edge allows localhost access by default starting with Windows 10 build 10166+. This can be disabled via "about:flags".

So that fixes it at least for the Edge browser.

Answer 2

Per the link in that same SO question, a future update will include the ability to enable localhost loopback support in about:flags.