I wanted to provide the new 'modern' web interface of traccar on a seperate domain without a new server instance.
- download https://github.com/traccar/traccar/releases/download/v$TRACCAR_VERSION/traccar-other-$TRACCAR_VERSION.zip
- unzip, move the ./web/modern directory to a location where your web server can access it and delete all other remaining files
- configure your webserver to serve the index.html
- configure your webserver to redirect or proxy the api and websocket requests to your server instance