MapLibre 6 and Mapbox GL 3 both throw out of their Map constructor without
WebGL2. Every place that builds a GL map now asks one helper first,
components/Map/glSupport.ts, and a browser without WebGL2 gets the Leaflet
map with the user's tiles instead of a map that fails to start:
- the trip map (MapViewAuto) and the journey maps (JourneyMapAuto) pick
their renderer through useGlRenderer, which folds in the Mapbox token
rule they each had;
- the settings preview, desktop and phone, shows the Leaflet preview
through useMapSettingsForm and says why under it;
- the tour planner keeps the 2D map when 3D is asked for and says that
3D needs WebGL2;
- the PDF route map and the Leaflet vector basemap already fell back and
now report a GPU failure too.
Behind the probe, buildGlMap wraps each constructor (MapViewGL,
JourneyMapGL, the settings preview, the terrain map, the PDF map). A GPU
that claims WebGL2 and still refuses the context is reported through
utils/webgl, which turns the answer to no and tells every mounted map,
so they switch to Leaflet without a reload; any other error is still
thrown. Two new strings, map.webgl2.fallback and map.webgl2.terrain, in
all 27 locales.
Maurice