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Dash Modal from dbc doesn't pop over the screen but below the last element on screen


I’m having an issue with the Modal components of Dash Bootstrap Components. When I click on the modal button, there is no modal window covering the screen appearing but rather a new element on the page below the button element (see the capture & the code below).


Has anyone ever encountered that issue? Is there a CSS element required to make the modal appear over the screen?

Thanks in advance,

import dash
from dash.dependencies import Input, Output, State
import dash_html_components as html
import dash_bootstrap_components as dbc

app = dash.Dash()

app.layout = html.Div([

        dbc.Button("Open modal", id="open"),
                dbc.ModalBody("This is the content of the modal"),
                    dbc.Button("Close", id="close", className="ml-auto"),


Output(“modal”, “is_open”),
[Input(“open”, “n_clicks”), Input(“close”, “n_clicks”)],
[State(“modal”, “is_open”)],
def toggle_modal(n1, n2, is_open):
if n1 or n2:
return not is_open
return is_open

if name == ‘main’:

You need to link a Bootstrap stylesheet. The easiest way is to do that in the Dash constructor using dbc.themes

app = dash.Dash(external_stylesheets=[dbc.themes.BOOTSTRAP])
1 Like

Hi mate,
Thanks for the quick answer! It works perfectly.
Have a nice day.

1 Like

How can i add new lines in dbc.ModalBody(‘Text in first line \n Text in second line’)

The result in the modal should be:

Text in first line
Text in second line

Please help me out. Thanks in advance.

Try this

dbc.ModalBody(["Text in first line",html.Br(),"Text in second line"])