Duplicate callback outputs when restarting the dash app

[hoatran]

@tararu

 @app.callback(
     Output("plot", "figure"), 
     [Input("plot-picker", "value"), Input("test-picker", "value")])

I see in your code this callback showed 2 times so I think it could be a reason. Try to delete one and I think it could work. If you want to use duplicate_callback you could refer this link about 2.9 version of Dash.

Dash 2.9.2 Released - Partial Property Updates with Patch(), Duplicate Outputs, dcc.Geolocation, Scatter Group Attributes and More

Update : version 2.11.0 has been released since this was posted. We’re excited to announce that Dash 2.9.2 has been released Register for the upcoming webinar to learn how to use the open-source feature. pip install dash==2.9.2 Official Changelog Dash v2.9.2 Highlights Partial Property Updates with Patch() Partial Property Updates can improve the performance of your Dash apps by preventing unnecessary computation, data fetching, and reducing …