Was using the VS desktop app but I also got the "localhost:5557 ERR_CONNECTION_REFUSED" error after the latest windows update. I tried the github "videostream port fix", disabling firewall, disabling anti-virus, uninstalling / reinstalling VS and Chrome, running the installer in Win7 compatibility mode - what finally worked for me was abandoning the desktop app and installing the VS app in Chrome from the Chrome Store.

Worked immediately.