Dash app not rendering after upgrading dash version to 1.13.3

Hi everyone, I’m new in Dash and I having this issue,

In the company I work for, we use Domino Data Lab as the development platform. I have a couple of web apps with Dash that were working ok but I recently change the working environment to upgrade dash from 0.39.0 to 1.13.3 and the app is not rendering anymore. I get no error messages but nothing is loading

RUN pip install dash==1.13.3 && \
    pip install plotly==4.5.4 && \
    pip install jupyterlab==0.35 "ipywidgets>=7.2"

and the app code is:

import dash
import dash_core_components as dcc
import dash_html_components as html
import pandas as pd
import plotly.graph_objs as go
import plotly as py
import plotly.express as px
from dash.dependencies import Input, Output

demand_df = pd.read_csv('demand_df')

demand_go =  demand_df[(demand_df['strength']=='120 mg')&(demand_df['run']==28)]
trace1=px.bar(demand_df[(demand_df['strength']=='40 mg')&(demand_df['run']==28)], x="period",y="value")
trace2=px.line(demand_df[demand_df['strength']=='100 mg'], x="period",y="value", color="run")
trace4=px.line(demand_df[demand_df['strength']=='240 mg'], x="period",y="value", color="run")

app = dash.Dash()
#app.config.requests_pathname_prefix = ''

#### as the proxy server may remove the prefix
'routes_pathname_prefix': '',

#### the front-end will prefix this string to the requests
#### that are made to the proxy server
'requests_pathname_prefix': ''
div_demand = html.Div(
        "display": "flex", "flex-direction": "column"}, children=[
            ], className="row"
                    #style={"width": "75%", "display": "inline-block"}
                ], className="three columns"),
            ], className="row"),
    ], className="mainContainer")
app.layout = div_demand    
    'external_url': 'https://codepen.io/chriddyp/pen/bWLwgP.css'
if __name__ == '__main__':
    app.run_server(port=8888, host='', debug=True)

Hey, did you ever manage to solve this issue? I am currently facing the same issue as well. Any help would be appreciated. Thanks!

hi @schua16 ,
welcome to the community.
Are you also trying to update to Dash 1.13.3 or the latest Dash version? And what’s happening after you upgrade, does it show a blank screen or do you get an error?