Widgets fail to render Debian 12 J Lab 4.3

Greetings all. I’m new here, instigated by an OS upgrade and migration from notebook to Lab. I have an ipywidgets GUI frontend for the pyEDM · PyPI package, and would like to bring it in compliance with J Lab.

However, a baseline example from the ipywidgets intro docs:

import ipywidgets as widgets
from IPython.display import display
w = widgets.IntSlider()
display(w)

does not render the widget, rather a text description:

IntSlider(value=0)

It seems something fundamental is amiss, or perhaps I am incorrectly using the methods.

Thank you!

System Info

~> lsb_release -a
No LSB modules are available.
Distributor ID:	Debian
Description:	Debian GNU/Linux 12 (bookworm)
Release:	12
Codename:	bookworm
~> uname -a
Linux xxx 6.1.0-28-amd64 #1 SMP PREEMPT_DYNAMIC Debian 6.1.119-1 (2024-11-22) x86_64 GNU/Linux

Environment

~> jupyter --version
Selected Jupyter core packages...
IPython          : 8.31.0
ipykernel        : 6.29.5
ipywidgets       : 8.1.5
jupyter_client   : 8.6.3
jupyter_core     : 5.7.2
jupyter_server   : 2.15.0
jupyterlab       : 4.3.4
nbclient         : 0.10.2
nbconvert        : 7.16.4
nbformat         : 5.10.4
notebook         : 7.3.2
qtconsole        : 5.6.1
traitlets        : 5.14.3
~> firefox --version
Mozilla Firefox 128.5.0esr