Scattermapbox maki symbols plot on map, but not legend

Hi Plotly,

First, thank you for all the fantastic work you do.

I am a big fan of / heavy user of the plotly.go objects that render maps (Scattermapbox / Choroplethmapbox).

I have noticed, however, that when setting the symbol type to a maki symbol, it will render it on the map - but not the legend. This feels like a bug, as there is also a colour associated with the legend item that is not matched anywhere on the plot / by the symbol (except in hovertext).

Reproducible example below:

import os
import plotly.graph_objects as go

mapboxt = os.getenv('MAPBOX_TOKEN') # a mapbox token

lats = [52.370216, 53.2191696,  50.851368, 51.8125626]
lons = [4.895168,  6.5666699, 5.690973, 5.8372264 ]

fig = go.Figure()

scatt = go.Scattermapbox(
            lat=lats,
            lon=lons,
            mode='markers',
            hovertext=['Amsterdam', 'Groningen',  'Maastricht', 'Nijmegen'],  
            hoverinfo='text',                 
            below='',                 
            marker=dict(symbol ='hospital'),
            name ='my_fake_hospitals',
            showlegend=True)

fig.add_trace(scatt)

fig.update_layout(go.Layout(title_text ='Is it a hospital? No, it is a blue dot!', 
                            title_x=0.5, 
                            width=750, 
                            height=700,
                            mapbox = dict(center= dict(lat=52.370216, lon=4.895168),            
                                         accesstoken= mapboxt,
                                         zoom=5,
                                         style="light"
                                       )))

fig

Finally, as a side note, some maki symbols plot whilst others do not. I have determined through trial and error that this is down to whether or not the MapBox style includes these specific symbol types. Using custom Mapbox styles, therefore, may silently break the maki functionality as well.

Thanks you for your attention.

Comienza ejecutando el ejemplo reproducible de Python proporcionado con Scattermapbox, el símbolo de Maki "hospital" y showlegend=True, y luego compara el símbolo del mapa con su elemento de leyenda. Sigue el manejo de marker-symbol y de la leyenda en Scattermapbox, incluida la nota sobre los estilos de Mapbox; se considera terminado cuando los símbolos de Maki compatibles aparecen de forma coherente en la leyenda y en el mapa, con el comportamiento cubierto por una prueba de regresión.