slow dropdown in dash

server.py

import dash
import dash_html_components as html
import dash_core_components as dcc

external_stylesheets = ['https://codepen.io/chriddyp/pen/bWLwgP.css']

app = dash.Dash(__name__, external_stylesheets=external_stylesheets)
app.layout = html.Div([
    dcc.Dropdown(
        id='dropdown-selector',
        options=[
            {'label' : 'no-dropdown', 'value' : 'no-dropdown' },
            {'label' : 'dropdown', 'value' : 'dropdown' }
        ],
        value='no-dropdown'
    ),
    html.Div(id='container')
])


@app.callback(
    dash.dependencies.Output('container', 'children'),
    [dash.dependencies.Input('dropdown-selector', 'value')])
def update_output(value):
    if value == "dropdown":
        return dcc.Dropdown(
            id='my-dropdown',
            options=[
                {'label': 'gene_{}'.format(i), 'value': 'gene_{}'.format(i)} for i in range(100000)
            ],
            multi=True
        )


if __name__ == '__main__':
    app.run_server(debug=True)