Ironic that the application won't load in Firefox without disabling Enhanced Tracking Protection because it relies on third party access to storage.
I think it just wasn't tested very well in Firefox. The third party map is blanking out for me at widths over 2048 pixels in a Firefox window. That's what I get for using an ultrawide monitor, I guess.
[0] https://mediaprogram.maps.arcgis.com/apps/instant/interactiv...