The package no longer automatically configures Leaflet's default marker icons. If you need to use default markers, you'll need to configure the icon URLs yourself. Add this configuration to your component or entry file:
import L from 'leaflet'
// Configure default marker icons
delete (L.Icon.Default as any).prototype._getIconUrl
L.Icon.Default.mergeOptions({
iconRetinaUrl: 'https://unpkg.com/leaflet@1.9.4/dist/images/marker-icon-2x.png',
iconUrl: 'https://unpkg.com/leaflet@1.9.4/dist/images/marker-icon.png',
shadowUrl: 'https://unpkg.com/leaflet@1.9.4/dist/images/marker-shadow.png',
})