Unable to get ipywidget web3 example working

[andrewphilipsmith]

Description

Unable to get ipywidget web3 example working

(Other notes: I posted this on discourse here https://discourse.jupyter.org/t/unable-to-get-ipywidget-web3-example-working/16601, but have had no response so far).

Reproduce

1. create and activate a new conda environment
2. clone ipywidgets
3. follow the ]setup instructions for the example “web3”](https://github.com/jupyter-widgets/ipywidgets/tree/master/examples/web3#try-it)
4. try opening the webpage (http://localhost:8080) in firefox, chrome or safari.
5. Check that the default value of the "Notebook BASEURL" matches the value given when starting the notebook server and then press OK.
6. A blank page is shown in the browser. (See JS Console output from each browser below).

Additionally, I have tried git checkout tags/8.0.2 immediately after cloning the repo (step 2) without effect.

I have tried recreating this several times and always get the same result. I do not have an opinion on whether this is an error is the web3 example itself or the documentation describing it.

Expected behaviour

Some visual indication of a widget being successfully loaded in the webpage.

Context

• ipywidgets version
  8.0.2

• Operating System and version:
  macOS 12.6.1 (21G217)

• Browser and version:
  Google Chrome Version 107.0.5304.87 (Official Build) (arm64)
  Firefox 106.0.3 (64-bit)

• Others (if required)
  yarn --version ==> 1.22.19
  conda --version ==> 22.9.0

Troubleshoot Output

Paste the output from running `jupyter troubleshoot` from the command line here.
You may want to sanitize the paths in the output.
$PATH:

</my/absolute/home>/anaconda3/envs/ipywidgets-test/bin

</my/absolute/home>/.cargo/bin

/opt/homebrew/opt/tcl-tk/bin

</my/absolute/home>/bin/google-cloud-sdk/bin

~/.gem/ruby/2.6.0/bin

/opt/local/bin

/opt/local/sbin

</my/absolute/home>/.poetry/bin

/opt/homebrew/bin

/opt/homebrew/sbin

</my/absolute/home>/.pyenv/shims

</my/absolute/home>/.pyenv/bin

</my/absolute/home>/anaconda3/condabin

/usr/local/bin

/usr/bin

/bin

/usr/sbin

/sbin

/opt/X11/bin

/usr/local/anaconda3/bin
sys.path:

</my/absolute/home>/anaconda3/envs/ipywidgets-test/bin

</my/absolute/home>/anaconda3/envs/ipywidgets-test/lib/python311.zip

</my/absolute/home>/anaconda3/envs/ipywidgets-test/lib/python3.11

</my/absolute/home>/anaconda3/envs/ipywidgets-test/lib/python3.11/lib-dynload

</my/absolute/home>/anaconda3/envs/ipywidgets-test/lib/python3.11/site-packages
sys.executable:

</my/absolute/home>/anaconda3/envs/ipywidgets-test/bin/python
sys.version:

3.11.0 | packaged by conda-forge | (main, Oct 25 2022, 06:24:51) [Clang 14.0.4 ]
platform.platform():

macOS-12.6.1-x86_64-i386-64bit
which -a jupyter:

</my/absolute/home>/anaconda3/envs/ipywidgets-test/bin/jupyter

</my/absolute/home>/.pyenv/shims/jupyter
pip list:

Package                       Version

----------------------------- -----------

anyio                         3.6.2

appnope                       0.1.3

argon2-cffi                   21.3.0

argon2-cffi-bindings          21.2.0

asttokens                     2.1.0

attrs                         22.1.0

Babel                         2.11.0

backcall                      0.2.0

backports.functools-lru-cache 1.6.4

beautifulsoup4                4.11.1

bleach                        5.0.1

brotlipy                      0.7.0

certifi                       2022.9.24

cffi                          1.15.1

charset-normalizer            2.1.1

cryptography                  38.0.3

debugpy                       1.6.3

decorator                     5.1.1

defusedxml                    0.7.1

entrypoints                   0.4

executing                     1.2.0

fastjsonschema                2.16.2

flit_core                     3.8.0

idna                          3.4

importlib-metadata            5.0.0

importlib-resources           5.10.0

ipykernel                     6.17.0

ipython                       8.6.0

ipython-genutils              0.2.0

ipywidgets                    8.0.2

jedi                          0.18.1

Jinja2                        3.1.2

json5                         0.9.5

jsonschema                    4.17.0

jupyter_client                7.4.4

jupyter_core                  4.11.2

jupyter-server                1.23.0

jupyterlab                    3.5.0

jupyterlab-pygments           0.2.2

jupyterlab_server             2.16.2

jupyterlab-widgets            3.0.3

MarkupSafe                    2.1.1

matplotlib-inline             0.1.6

mistune                       2.0.4

nbclassic                     0.4.8

nbclient                      0.7.0

nbconvert                     7.2.3

nbformat                      5.7.0

nest-asyncio                  1.5.6

notebook                      6.5.2

notebook_shim                 0.2.2

packaging                     21.3

pandocfilters                 1.5.0

parso                         0.8.3

pexpect                       4.8.0

pickleshare                   0.7.5

pip                           22.3.1

pkgutil_resolve_name          1.3.10

prometheus-client             0.15.0

prompt-toolkit                3.0.32

psutil                        5.9.4

ptyprocess                    0.7.0

pure-eval                     0.2.2

pycparser                     2.21

Pygments                      2.13.0

pyOpenSSL                     22.1.0

pyparsing                     3.0.9

pyrsistent                    0.19.2

PySocks                       1.7.1

python-dateutil               2.8.2

pytz                          2022.6

pyzmq                         24.0.1

requests                      2.28.1

Send2Trash                    1.8.0

setuptools                    65.5.1

six                           1.16.0

sniffio                       1.3.0

soupsieve                     2.3.2.post1

stack-data                    0.6.0

terminado                     0.17.0

tinycss2                      1.2.1

tomli                         2.0.1

tornado                       6.2

traitlets                     5.5.0

typing_extensions             4.4.0

urllib3                       1.26.11

wcwidth                       0.2.5

webencodings                  0.5.1

websocket-client              1.4.2

wheel                         0.38.3

widgetsnbextension            4.0.3

zipp                          3.10.0
conda list:

# packages in environment at </my/absolute/home>/anaconda3/envs/ipywidgets-test:

#

# Name                    Version                   Build  Channel

anyio                     3.6.2              pyhd8ed1ab_0    conda-forge

appnope                   0.1.3              pyhd8ed1ab_0    conda-forge

argon2-cffi               21.3.0             pyhd8ed1ab_0    conda-forge

argon2-cffi-bindings      21.2.0          py311h5547dcb_3    conda-forge

asttokens                 2.1.0              pyhd8ed1ab_0    conda-forge

attrs                     22.1.0             pyh71513ae_1    conda-forge

babel                     2.11.0             pyhd8ed1ab_0    conda-forge

backcall                  0.2.0              pyh9f0ad1d_0    conda-forge

backports                 1.0                        py_2    conda-forge

backports.functools_lru_cache 1.6.4              pyhd8ed1ab_0    conda-forge

beautifulsoup4            4.11.1             pyha770c72_0    conda-forge

bleach                    5.0.1              pyhd8ed1ab_0    conda-forge

brotlipy                  0.7.0           py311h5547dcb_1005    conda-forge

bzip2                     1.0.8                h0d85af4_4    conda-forge

ca-certificates           2022.9.24            h033912b_0    conda-forge

certifi                   2022.9.24          pyhd8ed1ab_0    conda-forge

cffi                      1.15.1          py311ha86e640_2    conda-forge

charset-normalizer        2.1.1              pyhd8ed1ab_0    conda-forge

cryptography              38.0.3          py311h61927ef_0    conda-forge

debugpy                   1.6.3           py311h814d153_1    conda-forge

decorator                 5.1.1              pyhd8ed1ab_0    conda-forge

defusedxml                0.7.1              pyhd8ed1ab_0    conda-forge

entrypoints               0.4                pyhd8ed1ab_0    conda-forge

executing                 1.2.0              pyhd8ed1ab_0    conda-forge

flit-core                 3.8.0              pyhd8ed1ab_0    conda-forge

idna                      3.4                pyhd8ed1ab_0    conda-forge

importlib-metadata        5.0.0              pyha770c72_1    conda-forge

importlib_resources       5.10.0             pyhd8ed1ab_0    conda-forge

ipykernel                 6.17.0             pyh736e0ef_0    conda-forge

ipython                   8.6.0              pyhd1c38e8_1    conda-forge

ipython_genutils          0.2.0                      py_1    conda-forge

ipywidgets                8.0.2                    pypi_0    pypi

jedi                      0.18.1             pyhd8ed1ab_2    conda-forge

jinja2                    3.1.2              pyhd8ed1ab_1    conda-forge

json5                     0.9.5              pyh9f0ad1d_0    conda-forge

jsonschema                4.17.0             pyhd8ed1ab_0    conda-forge

jupyter_client            7.4.4              pyhd8ed1ab_0    conda-forge

jupyter_core              4.11.2          py311h6eed73b_0    conda-forge

jupyter_server            1.23.0             pyhd8ed1ab_0    conda-forge

jupyterlab                3.5.0              pyhd8ed1ab_0    conda-forge

jupyterlab-widgets        3.0.3                    pypi_0    pypi

jupyterlab_pygments       0.2.2              pyhd8ed1ab_0    conda-forge

jupyterlab_server         2.16.2             pyhd8ed1ab_0    conda-forge

libcxx                    14.0.6               hccf4f1f_0    conda-forge

libffi                    3.4.2                h0d85af4_5    conda-forge

libsodium                 1.0.18               hbcb3906_1    conda-forge

libsqlite                 3.39.4               ha978bb4_0    conda-forge

libzlib                   1.2.13               hfd90126_4    conda-forge

markupsafe                2.1.1           py311h5547dcb_2    conda-forge

matplotlib-inline         0.1.6              pyhd8ed1ab_0    conda-forge

mistune                   2.0.4              pyhd8ed1ab_0    conda-forge

nbclassic                 0.4.8              pyhd8ed1ab_0    conda-forge

nbclient                  0.7.0              pyhd8ed1ab_0    conda-forge

nbconvert                 7.2.3              pyhd8ed1ab_0    conda-forge

nbconvert-core            7.2.3              pyhd8ed1ab_0    conda-forge

nbconvert-pandoc          7.2.3              pyhd8ed1ab_0    conda-forge

nbformat                  5.7.0              pyhd8ed1ab_0    conda-forge

ncurses                   6.3                  h96cf925_1    conda-forge

nest-asyncio              1.5.6              pyhd8ed1ab_0    conda-forge

notebook                  6.5.2              pyha770c72_1    conda-forge

notebook-shim             0.2.2              pyhd8ed1ab_0    conda-forge

openssl                   3.0.7                hfd90126_0    conda-forge

packaging                 21.3               pyhd8ed1ab_0    conda-forge

pandoc                    2.19.2               h694c41f_1    conda-forge

pandocfilters             1.5.0              pyhd8ed1ab_0    conda-forge

parso                     0.8.3              pyhd8ed1ab_0    conda-forge

pexpect                   4.8.0              pyh1a96a4e_2    conda-forge

pickleshare               0.7.5                   py_1003    conda-forge

pip                       22.3.1             pyhd8ed1ab_0    conda-forge

pkgutil-resolve-name      1.3.10             pyhd8ed1ab_0    conda-forge

prometheus_client         0.15.0             pyhd8ed1ab_0    conda-forge

prompt-toolkit            3.0.32             pyha770c72_0    conda-forge

psutil                    5.9.4           py311h5547dcb_0    conda-forge

ptyprocess                0.7.0              pyhd3deb0d_0    conda-forge

pure_eval                 0.2.2              pyhd8ed1ab_0    conda-forge

pycparser                 2.21               pyhd8ed1ab_0    conda-forge

pygments                  2.13.0             pyhd8ed1ab_0    conda-forge

pyopenssl                 22.1.0             pyhd8ed1ab_0    conda-forge

pyparsing                 3.0.9              pyhd8ed1ab_0    conda-forge

pyrsistent                0.19.2          py311h5547dcb_0    conda-forge

pysocks                   1.7.1              pyha2e5f31_6    conda-forge

python                    3.11.0          h559f36b_0_cpython    conda-forge

python-dateutil           2.8.2              pyhd8ed1ab_0    conda-forge

python-fastjsonschema     2.16.2             pyhd8ed1ab_0    conda-forge

python_abi                3.11                    2_cp311    conda-forge

pytz                      2022.6             pyhd8ed1ab_0    conda-forge

pyzmq                     24.0.1          py311habfacb3_1    conda-forge

readline                  8.1.2                h3899abd_0    conda-forge

requests                  2.28.1             pyhd8ed1ab_1    conda-forge

send2trash                1.8.0              pyhd8ed1ab_0    conda-forge

setuptools                65.5.1             pyhd8ed1ab_0    conda-forge

six                       1.16.0             pyh6c4a22f_0    conda-forge

sniffio                   1.3.0              pyhd8ed1ab_0    conda-forge

soupsieve                 2.3.2.post1        pyhd8ed1ab_0    conda-forge

stack_data                0.6.0              pyhd8ed1ab_0    conda-forge

terminado                 0.17.0             pyhd1c38e8_0    conda-forge

tinycss2                  1.2.1              pyhd8ed1ab_0    conda-forge

tk                        8.6.12               h5dbffcc_0    conda-forge

tomli                     2.0.1              pyhd8ed1ab_0    conda-forge

tornado                   6.2             py311h5547dcb_1    conda-forge

traitlets                 5.5.0              pyhd8ed1ab_0    conda-forge

typing_extensions         4.4.0              pyha770c72_0    conda-forge

tzdata                    2022f                h191b570_0    conda-forge

urllib3                   1.26.11            pyhd8ed1ab_0    conda-forge

wcwidth                   0.2.5              pyh9f0ad1d_2    conda-forge

webencodings              0.5.1                      py_1    conda-forge

websocket-client          1.4.2              pyhd8ed1ab_0    conda-forge

wheel                     0.38.3             pyhd8ed1ab_0    conda-forge

widgetsnbextension        4.0.3                    pypi_0    pypi

xz                        5.2.6                h775f41a_0    conda-forge

zeromq                    4.3.4                he49afe7_1    conda-forge

zipp                      3.10.0             pyhd8ed1ab_0    conda-forge
conda env:

name: ipywidgets-test

channels:

- conda-forge

- defaults

dependencies:

- anyio=3.6.2=pyhd8ed1ab_0

- appnope=0.1.3=pyhd8ed1ab_0

- argon2-cffi=21.3.0=pyhd8ed1ab_0

- argon2-cffi-bindings=21.2.0=py311h5547dcb_3

- asttokens=2.1.0=pyhd8ed1ab_0

- attrs=22.1.0=pyh71513ae_1

- babel=2.11.0=pyhd8ed1ab_0

- backcall=0.2.0=pyh9f0ad1d_0

- backports=1.0=py_2

- backports.functools_lru_cache=1.6.4=pyhd8ed1ab_0

- beautifulsoup4=4.11.1=pyha770c72_0

- bleach=5.0.1=pyhd8ed1ab_0

- brotlipy=0.7.0=py311h5547dcb_1005

- bzip2=1.0.8=h0d85af4_4

- ca-certificates=2022.9.24=h033912b_0

- certifi=2022.9.24=pyhd8ed1ab_0

- cffi=1.15.1=py311ha86e640_2

- charset-normalizer=2.1.1=pyhd8ed1ab_0

- cryptography=38.0.3=py311h61927ef_0

- debugpy=1.6.3=py311h814d153_1

- decorator=5.1.1=pyhd8ed1ab_0

- defusedxml=0.7.1=pyhd8ed1ab_0

- entrypoints=0.4=pyhd8ed1ab_0

- executing=1.2.0=pyhd8ed1ab_0

- flit-core=3.8.0=pyhd8ed1ab_0

- idna=3.4=pyhd8ed1ab_0

- importlib-metadata=5.0.0=pyha770c72_1

- importlib_resources=5.10.0=pyhd8ed1ab_0

- ipykernel=6.17.0=pyh736e0ef_0

- ipython=8.6.0=pyhd1c38e8_1

- ipython_genutils=0.2.0=py_1

- jedi=0.18.1=pyhd8ed1ab_2

- jinja2=3.1.2=pyhd8ed1ab_1

- json5=0.9.5=pyh9f0ad1d_0

- jsonschema=4.17.0=pyhd8ed1ab_0

- jupyter_client=7.4.4=pyhd8ed1ab_0

- jupyter_core=4.11.2=py311h6eed73b_0

- jupyter_server=1.23.0=pyhd8ed1ab_0

- jupyterlab=3.5.0=pyhd8ed1ab_0

- jupyterlab_pygments=0.2.2=pyhd8ed1ab_0

- jupyterlab_server=2.16.2=pyhd8ed1ab_0

- libcxx=14.0.6=hccf4f1f_0

- libffi=3.4.2=h0d85af4_5

- libsodium=1.0.18=hbcb3906_1

- libsqlite=3.39.4=ha978bb4_0

- libzlib=1.2.13=hfd90126_4

- markupsafe=2.1.1=py311h5547dcb_2

- matplotlib-inline=0.1.6=pyhd8ed1ab_0

- mistune=2.0.4=pyhd8ed1ab_0

- nbclassic=0.4.8=pyhd8ed1ab_0

- nbclient=0.7.0=pyhd8ed1ab_0

- nbconvert=7.2.3=pyhd8ed1ab_0

- nbconvert-core=7.2.3=pyhd8ed1ab_0

- nbconvert-pandoc=7.2.3=pyhd8ed1ab_0

- nbformat=5.7.0=pyhd8ed1ab_0

- ncurses=6.3=h96cf925_1

- nest-asyncio=1.5.6=pyhd8ed1ab_0

- notebook=6.5.2=pyha770c72_1

- notebook-shim=0.2.2=pyhd8ed1ab_0

- openssl=3.0.7=hfd90126_0

- packaging=21.3=pyhd8ed1ab_0

- pandoc=2.19.2=h694c41f_1

- pandocfilters=1.5.0=pyhd8ed1ab_0

- parso=0.8.3=pyhd8ed1ab_0

- pexpect=4.8.0=pyh1a96a4e_2

- pickleshare=0.7.5=py_1003

- pip=22.3.1=pyhd8ed1ab_0

- pkgutil-resolve-name=1.3.10=pyhd8ed1ab_0

- prometheus_client=0.15.0=pyhd8ed1ab_0

- prompt-toolkit=3.0.32=pyha770c72_0

- psutil=5.9.4=py311h5547dcb_0

- ptyprocess=0.7.0=pyhd3deb0d_0

- pure_eval=0.2.2=pyhd8ed1ab_0

- pycparser=2.21=pyhd8ed1ab_0

- pygments=2.13.0=pyhd8ed1ab_0

- pyopenssl=22.1.0=pyhd8ed1ab_0

- pyparsing=3.0.9=pyhd8ed1ab_0

- pyrsistent=0.19.2=py311h5547dcb_0

- pysocks=1.7.1=pyha2e5f31_6

- python=3.11.0=h559f36b_0_cpython

- python-dateutil=2.8.2=pyhd8ed1ab_0

- python-fastjsonschema=2.16.2=pyhd8ed1ab_0

- python_abi=3.11=2_cp311

- pytz=2022.6=pyhd8ed1ab_0

- pyzmq=24.0.1=py311habfacb3_1

- readline=8.1.2=h3899abd_0

- requests=2.28.1=pyhd8ed1ab_1

- send2trash=1.8.0=pyhd8ed1ab_0

- setuptools=65.5.1=pyhd8ed1ab_0

- six=1.16.0=pyh6c4a22f_0

- sniffio=1.3.0=pyhd8ed1ab_0

- soupsieve=2.3.2.post1=pyhd8ed1ab_0

- stack_data=0.6.0=pyhd8ed1ab_0

- terminado=0.17.0=pyhd1c38e8_0

- tinycss2=1.2.1=pyhd8ed1ab_0

- tk=8.6.12=h5dbffcc_0

- tomli=2.0.1=pyhd8ed1ab_0

- tornado=6.2=py311h5547dcb_1

- traitlets=5.5.0=pyhd8ed1ab_0

- typing_extensions=4.4.0=pyha770c72_0

- tzdata=2022f=h191b570_0

- urllib3=1.26.11=pyhd8ed1ab_0

- wcwidth=0.2.5=pyh9f0ad1d_2

- webencodings=0.5.1=py_1

- websocket-client=1.4.2=pyhd8ed1ab_0

- wheel=0.38.3=pyhd8ed1ab_0

- xz=5.2.6=h775f41a_0

- zeromq=4.3.4=he49afe7_1

- zipp=3.10.0=pyhd8ed1ab_0

- pip:

- ipywidgets==8.0.2

- jupyterlab-widgets==3.0.3

- widgetsnbextension==4.0.3

prefix: </my/absolute/home>/anaconda3/envs/ipywidgets-test

Command Line Output

Paste the output from your command line running `jupyter lab` (or `jupyter notebook` if you use notebook) here, use `--debug` if possible.
$ jupyter lab

[I 2022-11-09 17:04:48.004 ServerApp] jupyterlab | extension was successfully linked.

[I 2022-11-09 17:04:48.010 ServerApp] nbclassic | extension was successfully linked.

[I 2022-11-09 17:04:48.210 ServerApp] notebook_shim | extension was successfully linked.

[I 2022-11-09 17:04:48.258 ServerApp] notebook_shim | extension was successfully loaded.

[I 2022-11-09 17:04:48.259 LabApp] JupyterLab extension loaded from </my/absolute/home>/anaconda3/envs/ipywidgets-test/lib/python3.11/site-packages/jupyterlab

[I 2022-11-09 17:04:48.259 LabApp] JupyterLab application directory is </my/absolute/home>/anaconda3/envs/ipywidgets-test/share/jupyter/lab

[I 2022-11-09 17:04:48.261 ServerApp] jupyterlab | extension was successfully loaded.

[I 2022-11-09 17:04:48.264 ServerApp] nbclassic | extension was successfully loaded.

[I 2022-11-09 17:04:48.266 ServerApp] Serving notebooks from local directory: </my/absolute/home>/code/long-nlp/ipywidgets/examples/web3

[I 2022-11-09 17:04:48.267 ServerApp] Jupyter Server 1.23.0 is running at:

[I 2022-11-09 17:04:48.267 ServerApp] http://localhost:8888/lab?token=<my_token>

[I 2022-11-09 17:04:48.267 ServerApp]  or http://127.0.0.1:8888/lab?token=<my_token>

[I 2022-11-09 17:04:48.267 ServerApp] Use Control-C to stop this server and shut down all kernels (twice to skip confirmation).

[C 2022-11-09 17:04:48.281 ServerApp]
To access the server, open this file in a browser:
    file://</my/absolute/home>/Library/Jupyter/runtime/jpserver-9300-open.html
Or copy and paste one of these URLs:
    http://localhost:8888/lab?token=<my_token>
 or http://127.0.0.1:8888/lab?token=<my_token>

0.00s - Debugger warning: It seems that frozen modules are being used, which may

0.00s - make the debugger miss breakpoints. Please pass -Xfrozen_modules=off

0.00s - to python to disable frozen modules.

0.00s - Note: Debugging will proceed. Set PYDEVD_DISABLE_FILE_VALIDATION=1 to disable this validation.

[I 2022-11-09 17:04:51.789 LabApp] Build is up to date

Browser Output

Paste the output from your browser Javascript console here.
Firefox:

16:40:16.584 This page is in Quirks Mode. Page layout may be impacted. For Standards Mode use “”.

127.0.0.1:8080

16:40:16.901 Download the React DevTools for a better development experience: https://reactjs.org/link/react-devtools react-dom.development.js:26244

16:40:16.955 strict mode: use allowUnionTypes to allow union type keyword at "#/properties/state/additionalProperties/properties/buffers/items/properties/path/items" (strictTypes) util.js:175

16:40:16.958 Layout was forced before the page was fully loaded. If stylesheets are not yet loaded this may cause a flash of unstyled content. index.js:7

16:40:19.930 Uncaught (in promise) ReferenceError: process is not defined

makeSettings serverconnection.js:156

makeSettings serverconnection.js:53

 index.js:15

serverconnection.js:156
Chrome

util.js:175 strict mode: use allowUnionTypes to allow union type keyword at "#/properties/state/additionalProperties/properties/buffers/items/properties/path/items" (strictTypes)

checkStrictMode @ util.js:175

serverconnection.js:156 Uncaught (in promise) ReferenceError: process is not defined

at Object.makeSettings (serverconnection.js:156:1)

at Object.makeSettings (serverconnection.js:53:1)

at HTMLDocument. (index.js:15:28)

:8080/favicon.ico:1          Failed to load resource: the server responded with a status of 404 (Not Found)

If using JupyterLab

• JupyterLab version:

Installed Labextensions

Paste the output from your command line running `jupyter labextension list`.
    jupyterlab_pygments v0.2.2 enabled OK (python, jupyterlab_pygments)
    @jupyter-widgets/jupyterlab-manager v5.0.3 enabled OK (python, jupyterlab_widgets)

[samrat]

I also get the same error. Looks like this is caused due to a bug in jupyterlab and was fixed in jupyterlab/jupyterlab#12213 but the example project is still using an older version of the dependency.

[jasongrout]

Until we upgrade to the latest JupyterLab services package, we can work around this by introducing this config to define the process variable in the web3 example webpack config: https://github.com/jupyterlab/jupyterlab/blob/72f89c9e7015dc3a79c6b5e2d6e2e479d9a8b926/examples/notebook/webpack.config.js#L46-L51