Data Security with Plotly+Mapbox

When using plotly Scattermapbox, is the data being plotted on top of the map ever sent to an external server (e.g. via the mapbox API call)?

If I understand correctly, the mapbox API is used just to render the tiles, and this has three parameters - x,y of the tile centre, and zoom level. So, other than the implicit location of the tile, none of the scatter points are being sent?

Having trouble verifying this myself by going through the Mapbox wrapper, which itself is in fact in plotly.js(?)

Appreciate any insights. Thank you!