I am refering to this question. I face the same issue with Chrome Version 79.0.3945.117.
If I visit the dash plotly gallery- Oil and Gas example the map is not displayed but it is still rendered (as the legend is displayed). The same issue occurs for my own project as well.
I guess this has nothing to do with the Mapbox Token, as the charts get displayed correctly in other browsers or in chrome when I use another machine.
Any help much appreciated!