I created a BasemapGallery with LocalBasemapsSource from map service hosted in GIS Server:
const myBasemaps = [
new TileLayer({
url: "https://myhost.com/arcgis/rest/services/OCPA/Aerials2023/MapServer"
})
];
const basemapGallery = new BasemapGallery({
view: this.view,
container: "basemap-gallery",
source: new LocalBasemapsSource({
basemaps: myBasemaps
})
});
How to setup Tooltips like:

Thanks.
Forrest