The ability to add allow=loopback-network to the add-ons enclosing iframe

We are developing an add-on that integrates with our software over a local websocket. In development this is working great -- We are able to maintain a constant connection and transfer data between the local agent into Express. Recently Chrome (and most chrome based browsers) have started restricting local websocket connections that are not specifically allowed. Adding `allow=”loopback-network”` to the parent iframe should prompt the user to accept the connection and allow our integration to function as desired. The current workaround is to turn off the flag ‘local-network-access-check-websockets’ flag in Chrome, but this is not acceptable in a shipping product. As of this writing, Firefox does not have this restriction. I imagine it surfacing as a manifest declaration we are able to use with our add-on.

Thank you for your consideration.