Widgets showing as text in JupyterLab 4.x

JupyterLab
1

Hi,

I’ve seen this issue come across on several forums, though none of the solutions mentioned there seem to have worked for me.

When trying to visualise a simple widget in Jupyterlab 4.5.6 I get text as output:

import ipywidgets as widgets

widgets.IntSlider()

returns IntSlider(value=0) instead of a slider.

Below are my installed packages and lab extensions.

anyio                     4.13.0
argon2-cffi               25.1.0
argon2-cffi-bindings      25.1.0
arrow                     1.4.0
asttokens                 3.0.1
async-lru                 2.3.0
attrs                     26.1.0
babel                     2.18.0
beautifulsoup4            4.14.3
bleach                    6.3.0
certifi                   2026.2.25
cffi                      2.0.0
charset-normalizer        3.4.7
colorama                  0.4.6
comm                      0.2.3
debugpy                   1.8.20
decorator                 5.2.1
defusedxml                0.7.1
executing                 2.2.1
fastjsonschema            2.21.2
fqdn                      1.5.1
h11                       0.16.0
httpcore                  1.0.9
httpx                     0.28.1
idna                      3.11
ipykernel                 7.2.0
ipython                   9.12.0
ipython_pygments_lexers   1.1.1
ipywidgets                8.1.8
isoduration               20.11.0
jedi                      0.19.2
Jinja2                    3.1.6
json5                     0.14.0
jsonpointer               3.1.1
jsonschema                4.26.0
jsonschema-specifications 2025.9.1
jupyter                   1.1.1
jupyter_client            8.8.0
jupyter-console           6.6.3
jupyter_core              5.9.1
jupyter-events            0.12.0
jupyter-lsp               2.3.1
jupyter_server            2.17.0
jupyter_server_terminals  0.5.4
jupyterlab                4.5.6
jupyterlab_pygments       0.3.0
jupyterlab_server         2.28.0
jupyterlab_widgets        3.0.16
lark                      1.3.1
MarkupSafe                3.0.3
matplotlib-inline         0.2.1
mistune                   3.2.0
nbclient                  0.10.4
nbconvert                 7.17.1
nbformat                  5.10.4
nest-asyncio              1.6.0
notebook                  7.5.5
notebook_shim             0.2.4
packaging                 26.1
pandocfilters             1.5.1
parso                     0.8.6
pip                       23.2.1
platformdirs              4.9.6
prometheus_client         0.25.0
prompt_toolkit            3.0.52
psutil                    7.2.2
pure_eval                 0.2.3
pycparser                 3.0
Pygments                  2.20.0
python-dateutil           2.9.0.post0
python-json-logger        4.1.0
pywinpty                  3.0.3
PyYAML                    6.0.3
pyzmq                     27.1.0
referencing               0.37.0
requests                  2.33.1
rfc3339-validator         0.1.4
rfc3986-validator         0.1.1
rfc3987-syntax            1.1.0
rpds-py                   0.30.0
Send2Trash                2.1.0
setuptools                82.0.1
six                       1.17.0
soupsieve                 2.8.3
stack-data                0.6.3
terminado                 0.18.1
tinycss2                  1.4.0
tornado                   6.5.5
traitlets                 5.14.3
typing_extensions         4.15.0
tzdata                    2026.1
uri-template              1.3.0
urllib3                   2.6.3
wcwidth                   0.6.0
webcolors                 25.10.0
webencodings              0.5.1
websocket-client          1.9.0
widgetsnbextension        4.0.15

JupyterLab v4.5.6
jupyterlab_pygments v0.3.0 enabled ok (python, jupyterlab_pygments)
@jupyter-notebook/lab-extension v7.5.5 enabled ok
@jupyter-widgets/jupyterlab-manager v5.0.15 enabled ok

2

Without:

  • the platform
  • the install mechanism (e.g. pip/uv with/without user, conda/mamba/pixi)
  • some browser/server network logs

…it’s hard to diagnose further.

1 Like