I want remove ‘trace0’ showing on the map. How to use hovertemplate to remove this? And before I use hovertemplate, do I need to specify hovername?
The hovertemplate is a string that sets what is displayed on hover. If you want to display some data that is not used in the trace definition, then you can define the customdata for that trace` https://plotly.com/~empet/15366/customdata-for-a-few-plotly-chart-types/#/
To avoid displaying the trace name (trace0) on hover, insert at the end of the hovertemplate string,
'<extra></extra>'.