Long callbacks not working in JupyterDash (no PID found)

I just tried adding a long callback to a JupyterDash app and it looks like the ‘running options’ are not working correctly.
Here is example 2 from the official guide changed to run with JupyterDash:

from jupyter_dash import JupyterDash
import time
import dash
from dash import html
from dash.long_callback import DiskcacheLongCallbackManager
from dash.dependencies import Input, Output

## Diskcache
import diskcache

cache = diskcache.Cache("./cache")
long_callback_manager = DiskcacheLongCallbackManager(cache)

app = JupyterDash(__name__, long_callback_manager=long_callback_manager)

app.layout = html.Div(
        html.Div([html.P(id="paragraph_id", children=["Button not clicked"])]),
        html.Button(id="button_id", children="Run Job!"),

    output=Output("paragraph_id", "children"),
    inputs=Input("button_id", "n_clicks"),
        (Output("button_id", "disabled"), True, False),
def callback(n_clicks):
    return [f"Clicked {n_clicks} times"]

if __name__ == "__main__":
    app.run_server(debug=True, mode='inline', port=2006)

The button is disabled straight away on start and it’s never re-enabled. After a while I can see this exception shown in the cell output:

ProcessLookupError: [Errno 3] assume no such process (originated from NtQuerySystemInformation (no PID found))

During handling of the above exception, another exception occurred:

NoSuchProcess                             Traceback (most recent call last)
NoSuchProcess: psutil.NoSuchProcess process no longer exists (pid=10268)

Similar problem with example 3, there the output doesn’t get set and it also prints a similar exception

This is a bug. Thank you for reporting this, @kiteme .

Would you like to report this bug on our Dash repo as a new issue?

ok: [BUG] Long callback doesn't work in jupyter notebook · Issue #2056 · plotly/dash · GitHub

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