Microsoft Edge does not allow localhost loopback for websockets

In the Microsoft Edge browser type "About:flags" in the title bar (search bar). No quotes, Tick/Un-tick the "allow Localhost Loopback" feature.

Edge on Win Build 10240. (still works upto New Edge (chrome based))


After some research I found the source of error. Here is my repo, to reproduce error: https://github.com/AZaviruha/ms-edge-ws-strange

In short, when you call new WebSocket in MS Edge, it does not generate exception, when you call it with wrong "local"-host argument:

var socket, path;
var hosts = ['localhost', '127.0.0.1'];

for (var i in hosts) {
    path = 'ws://'+hosts[i]+':9446';
    console.log( '===> Tested path :: ', path );
    try {
        socket = new WebSocket( path );
        break;
    }
    catch ( e ) {
        // !!! Never shown !!!
        console.error( '===> WebSocket creation error :: ', e );
    }
}

Because of this, you can't "retry" to connect with different hosts.

By the way, if you try non-local non-existent host, it will generate exception!