UWP: Servo can’t load http://localhost:56012/

[paulrouget]

Servo loads for a pretty long time, and end up showing this message:

No problem on Firefox.

class handler(BaseHTTPRequestHandler):
    def do_GET(self):
        self.send_response(200)
        self.send_header('Content-type','text/html')
        self.end_headers()
        self.wfile.write("Hello")
        return
server = HTTPServer(('', 56012), handler)
server_thread = threading.Thread(target=server.serve_forever)
server_thread.start()

[paulrouget]

If I run the same python code on a different machine, no problem. So it’s likely to be another issue with the UWP Network Isolation protection.

[paulrouget]

Yes, it’s a UWP limitation. It’s possible to work around it temporarily:

checknetisolation loopbackexempt -a -n="$(Get-AppxPackage -Name MozillaFoundation.FirefoxReality)"'