Handle NDJSON Stream Promises in Stache Can.js

Question

I have this streaming API endpoint:

https://step3-ndjson-stream-api-demo.glitch.me/

I try to render with can.js NDJSON stream and following the example got some success output to console.log but only the first object.

Here's my app.js (truncated):

const AppViewModel = DefineMap.extend("AppViewModel", {
  // misc. properties, then
  get streamFunct(){
      return fetch(
        'https://step3-ndjson-stream-api-demo.glitch.me/'
      ).then(function(response){
        return ndjsonStream( response.body );
      }).then( ( streamData ) => {

        const reader = streamData.getReader();
        let read;

        reader.read().then( read = ( result ) => {
            if ( result.done ) {
                return;
            }
            console.log( result.value );
            streamData.getReader().read().then( read );
        } );
    } );
  }
});

And here's a snippet from my index.stache:

<p>Stream Data: <strong>{{streamFunct}}</strong></p>

And my console developer view (note the successful first call):

I think I have to handle the promise object in the index.stache but not sure... Thank you for looking.

UPDATE

Finally I'm able to get the streamed data:

  get streamFunct(){
  return fetch(
    'https://step3-ndjson-stream-api-demo.glitch.me/'
  ).then(function(response){
    return ndjsonStream( response.body );
  }).then( ( streamData ) => {

    //retain access to the reader so that you can cancel it
    const reader = streamData.getReader();
    const listResult = document.querySelector('.displayResult ul')
    let read;

    reader.read().then( read = ( result ) => {
        if ( result.done ) {
            console.log('Failed to find match');
            return;
        }
        const chunk = result.value;
        let listItem = document.createElement('li');
        listItem.textContent = chunk.user;
        listResult.appendChild(listItem);
        
        return reader.read().then(read);
    } ).catch ((error) => {
      console.log(error);
    });
} );

}

And modify my index.stache:

<p>Stream Data:</p>
<div class="displayResult">
<ul>

</ul>
</div>

But I still got errors/warnings:

UnhandledPromiseRejectionWarning: Error [ERR_HTTP_HEADERS_SENT]: Cannot set headers after they are sent to the client

[DEP0018] DeprecationWarning: Unhandled promise rejections are deprecated. In the future, promise rejections that are not handled will terminate the Node.js process with a non-zero exit code.

Failed promise: TypeError: response.getReader is not a function

Does anyone know how to clear them?