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.

Beginnen Sie damit, das bereitgestellte reproduzierbare Python-Beispiel mit Scattermapbox, dem Maki-Symbol "hospital" und showlegend=True auszuführen, und vergleichen Sie dann das Kartensymbol mit seinem Legendeneintrag. Verfolgen Sie die Handhabung von Scattermapbox-Marker-Symbolen und der Legende, einschließlich des Hinweises zu Mapbox-Stilen; als abgeschlossen gilt die Aufgabe, wenn unterstützte Maki-Symbole konsistent in der Legende und auf der Karte erscheinen und das Verhalten durch einen Regressionstest abgedeckt ist.