Why is the Cesium ION logo showing up?

Using Cesium Sandcastle

if I have:

HTML body & css

<style>
  @import url(../templates/bucket.css);
</style>
<div id="cesiumContainer" class="fullSize"></div>
<div id="loadingOverlay"><h1>Loading...</h1></div>
<div id="toolbar"></div>    

JavaScript Code:

const osm = new Cesium.OpenStreetMapImageryProvider({
  url : 'https://a.tile.openstreetmap.org/'
});


const viewer = new Cesium.Viewer("cesiumContainer", {
  baseLayer: Cesium.ImageryLayer.fromProviderAsync(osm),
  baseLayerPicker: false,
  geocoder: false,
});

It is my understanding that I should not be using Cesium ion. Is this correct?

However, what appears in the window contains the logo and text for Cesium ion:

image

I assume I am missing some configuration option that would allow me to either not show the logo or have it show the correct one which just says “Cesium” or something.

What am I missing?