It uses Mapbox GL JS v2.x, which is no longer open-source and is tied to the TOS, so the distinction of using Mapbox tiles or not doesn't seem to matter. Just l

It uses Mapbox GL JS v2.x, which is no longer open-source and is tied to the TOS, so the distinction of using Mapbox tiles or not doesn't seem to matter. Just loading the library requires a token from Mapbox.