Use-case demo
Place picker
The browser never talks to a maps SDK. The combobox queries an
application datasource (load(query, { signal })), renders
provider-neutral { value, label, data } items, and
materializes only the selected transient result into the native
<select>. Swap the provider (Google / Mapbox /
Nominatim / internal API) without touching the renderer.
Contract under test here is the datasource (query + AbortSignal →
items), not any maps API: this page uses an async fake provider
with an abortable delay. In production load() would
fetch() an application endpoint that normalizes the third
party response into the neutral shape below.
Fallback: remote loading is enhanced-mode only. Without enhancement this degrades to a plain native select with its placeholder option.