Why do WidgetSettings get stored in "mobile" array element

[zappingseb]

Please see this line:

plugin-google-maps-widget/resources/views/Widgets/MapsWidget.twig

Line 3 in d39dfd6

<google-maps-widget class="widget widget-proportional" google-api-key="{{ geocoding_data.apiKey }}" address="{{ geocoding_data.address }}" :lat="{{ geocoding_data.lat }}" :lng="{{ geocoding_data.lng }}" :zoom="{{ widget.settings.zoom.mobile | default(16) }}"></google-maps-widget>

I do not understand why the settings are stored in ["mobile"] or .mobile.