Hass Core - "Reverse Proxy" Z-Wave JS in Nabucasa frontend

I’m running Hass Core on my own Linux setup because Reasons™️.

I’ve put in a custom sidebar that will open up the ZWaveJS URL (a 10.0.0.X address) in a new tab, but this only works when I’m on my local network.

I have seen in Hass OS you are able to have the various components open as a frame “inside” the home assistant UI, which is great when you’re off network and can re-use the Nabu Casa frontend.

How can I do this with Hass Core?

Short answer, you can’t

That feature requires the Supervisor and only works for add-ons. It uses the ingress feature of the Supervisor.