I have same problem but just trying to build it run it in local server after build from React ( npm -s build) and the map only display the image (no street names, places etc) and cant fetch the elevation for each point in a route, it gives me Zero values (this is what my app has to do it). I works fine in npm start (testing mode) I tried the import mapboxgl from '!mapbox-gl', but didnt fix the problem. Is there any other recommendation? The token i use is default public one