No port forwarding for "code serve-web" when accessed from another machine #316209

On another machine on my network, I ran:

code serve-web --host 0.0.0.0 --port 9000

This serves the web version of VS Code and I can access it from my own machine (by using the other machines IP address/hostname).

However, extension calls to vscode.env.asExternalUri() with a localhost URI to not get forwarded or mapped in any way, so the extension tries to load webviews with localhost URLs that fail on the client machine.

VS Code knows the correct host/IP being used to access the UI (vscode.env.remoteName shows the name of the other machine which I'm using in the address bar) so I would've thought it could forward the port and rewrite the URL (at least behind a CLI flag).