# Missing Debugger Option

**URL:** <https://discourse.jupyter.org/t/missing-debugger-option/9851>\
**Category:** JupyterLab\
**Created:** [July 3, 2021, 10:08pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851 "2021-07-03T22:08:22Z")\
**Posts on this page:** 18\
**Page:** 1

<div class="post-metadata">

**Author:** ![matt](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/matt/32/4710_2.png) [@matt](https://discourse.jupyter.org/u/matt)\
**Post date:** [July 3, 2021, 10:08pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/1 "2021-07-03T22:08:22Z")

</div>

I have JupyterLab 3.0.16 and ipyKernel 6.0 but yet do not see the Enable Debugger option in the top right next to python3 (ipykernel).

 ![image](https://canada1.discourse-cdn.com/flex031/uploads/jupyter/original/2X/b/b86efcb27e6c9c8b8ae95e00e29563e8bac973bb.png)

I believe I have all the packages. Are there extensions that need to be enabled?

My packages are:

Package Version Location

* * *

anyio 3.2.1  
appmode 0.8.0  
argon2-cffi 20.1.0  
async-generator 1.10  
attrs 21.2.0  
Babel 2.9.1  
backcall 0.2.0  
beautifulsoup4 4.9.3  
bleach 3.3.0  
certifi 2021.5.30  
cffi 1.14.5  
chardet 4.0.0  
cron-descriptor 1.2.24  
cryptography 3.4.4  
cycler 0.10.0  
debugpy 1.3.0  
decorator 5.0.9  
defusedxml 0.7.1  
Deprecated 1.2.6  
entrypoints 0.3  
idna 2.10  
ipykernel 6.0.1  
ipython 7.25.0  
ipython-genutils 0.2.0  
ipyvue 1.5.0  
ipyvuetify 1.7.0  
ipywidgets 7.6.3  
jedi 0.18.0  
Jinja2 3.0.1  
json5 0.9.6  
jsonschema 3.2.0  
jupyter-client 6.1.12  
jupyter-core 4.7.1  
jupyter-server 1.9.0  
jupyterlab 3.0.16  
jupyterlab-pygments 0.1.2  
jupyterlab-server 2.6.0  
jupyterlab-widgets 1.0.0  
kiwisolver 1.3.1  
Mako 1.1.4  
MarkupSafe 2.0.1  
matplotlib 3.4.2  
matplotlib-inline 0.1.2  
mistune 0.8.4  
nbclassic 0.3.1  
nbclient 0.5.3  
nbconvert 6.1.0  
nbformat 5.1.3  
nest-asyncio 1.5.1  
notebook 6.4.0  
numpy 1.20.3  
p2j 1.3.2  
packaging 21.0  
pandas 1.2.4  
pandocfilters 1.4.3  
parsedatetime 2.6  
parso 0.8.2  
pexpect 4.8.0  
pickleshare 0.7.5  
Pillow 8.3.0  
pip 21.1.2  
plotly 4.14.3  
prometheus-client 0.11.0  
prompt-toolkit 3.0.19  
ptyprocess 0.7.0  
pycparser 2.20  
Pygments 2.9.0  
pyOpenSSL 20.0.1  
pyparsing 2.4.7  
pyrsistent 0.18.0  
python-dateutil 2.8.1  
pytz 2021.1  
pyzmq 22.1.0  
recurrent 0.4.0  
requests 2.25.1  
requests-unixsocket 0.2.0  
retrying 1.3.3  
scipy 1.6.3  
Send2Trash 1.7.1  
setuptools 57.0.0  
six 1.16.0  
sniffio 1.2.0  
soupsieve 2.2.1  
terminado 0.10.1  
testpath 0.5.0  
tornado 6.1  
traitlets 5.0.5  
tzlocal 2.0.0  
urllib3 1.26.6  
wcwidth 0.2.5  
webencodings 0.5.1  
websocket-client 1.1.0  
wheel 0.36.2  
widgetsnbextension 3.5.1  
wrapt 1.12.1

---

<div class="post-metadata">

**Author:** ![krassowski](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/krassowski/32/1685_2.png) [@krassowski](https://discourse.jupyter.org/u/krassowski)\
**Post date:** [July 3, 2021, 11:30pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/2 "2021-07-03T23:30:36Z")

</div>

That’s strange. For me it sometimes takes a few seconds to show up but it is working with similar package versions. Is there a debugger icon in the sidebar? Are there any error messages in the web developer console, or in the terminal from which the JupyterLab was started?

---

<div class="post-metadata">

**Author:** ![matt](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/matt/32/4710_2.png) [@matt](https://discourse.jupyter.org/u/matt)\
**Post date:** [July 4, 2021, 1:14am UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/3 "2021-07-04T01:14:07Z")

</div>

No errors in the terminal where it was started. I am running from a Docker image calling: “jupyter notebook” with JUPYTER\_ENABLE\_LAB=yes if that matters

Here is screen shot of web console. There are some content blockers for the npmjs extension registry and 2 fetch errors in PUT commands. Both debug to same spot you see in debugger.

 ![image](https://canada1.discourse-cdn.com/flex031/uploads/jupyter/original/2X/1/15b101222af34e82b577245b61734abed6eb09d8.png)

From the calling terminal here are all warnings/errors:

```auto
        [W 2021-07-04 00:48:47.533 LabApp] 'allow_origin_pat' has moved from NotebookApp to ServerApp. This config will be passed to ServerApp. Be sure to update your config before our next release.
        [W 2021-07-04 00:48:47.533 LabApp] 'base_url' has moved from NotebookApp to ServerApp. This config will be passed to ServerApp. Be sure to update your config before our next release.
[W 2021-07-04 00:48:47.533 LabApp] 'terminals_enabled' has moved from NotebookApp to ServerApp. This config will be passed to ServerApp. Be sure to update your config before our next release.
[W 2021-07-04 00:48:47.533 LabApp] 'terminals_enabled' has moved from NotebookApp to ServerApp. This config will be passed to ServerApp. Be sure to update your config before our next release.
        [W 2021-07-04 00:48:47.533 LabApp] 'ip' has moved from NotebookApp to ServerApp. This config will be passed to ServerApp. Be sure to update your config before our next release.
        [W 2021-07-04 00:48:47.533 LabApp] 'token' has moved from NotebookApp to ServerApp. This config will be passed to ServerApp. Be sure to update your config before our next release.
[W 2021-07-04 00:48:47.534 LabApp] 'allow_remote_access' has moved from NotebookApp to ServerApp. This config will be passed to ServerApp. Be sure to update your config before our next release.
	[W 2021-07-04 00:58:14.588 LabApp] Could not determine jupyterlab build status without nodejs
       [W 00:49:42.417 NotebookApp] No such channel: 'control'

```

---

<div class="post-metadata">

**Author:** ![krassowski](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/krassowski/32/1685_2.png) [@krassowski](https://discourse.jupyter.org/u/krassowski)\
**Post date:** [July 4, 2021, 12:12pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/4 "2021-07-04T12:12:25Z")

</div>

I don’t know enough about the debugger but I think that the last message `[W 00:49:42.417 NotebookApp] No such channel: 'control'` and the use of the `notebook` server instead of `jupyter_server` might be related. I think if @jtp or @JohanMabille might be able to clarify if `jupyter_server` is needed for the debugger to work correctly (or how to fix the lack of control channel availability).

---

<div class="post-metadata">

**Author:** ![matt](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/matt/32/4710_2.png) [@matt](https://discourse.jupyter.org/u/matt)\
**Post date:** [July 5, 2021, 12:48am UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/5 "2021-07-05T00:48:30Z")

</div>

I switched to calling :jupyter lab" instead of notebook and still do not see debugger option. I am still seeing the missing ‘control’ error but from ServerApp instead of NotebookApp.

```auto
[W 2021-07-05 00:45:04.226 ServerApp] No such channel: 'control'

```

---

<div class="post-metadata">

**Author:** ![matt](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/matt/32/4710_2.png) [@matt](https://discourse.jupyter.org/u/matt)\
**Post date:** [July 12, 2021, 8:57pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/6 "2021-07-12T20:57:33Z")

</div>

Can anyone advise as to why I am getting a No such channel: ‘control’ error? Thanks

---

<div class="post-metadata">

**Author:** ![krassowski](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/krassowski/32/1685_2.png) [@krassowski](https://discourse.jupyter.org/u/krassowski)\
**Post date:** [July 13, 2021, 8:57am UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/7 "2021-07-13T08:57:48Z")

</div>

See [jupyterlab/jupyterlab - Gitter](https://gitter.im/jupyterlab/jupyterlab?at=60ed4415f1274d5e5046c02e). I would advise to try creating a fresh virtual environment; If you are using conda, I think that some of the packages might be loaded from a different path, otherwise some of the packages might be outdated but it is hard for me to pinpoint which one to update, so I would just create a fresh env.

---

<div class="post-metadata">

**Author:** ![jtp](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/jtp/32/19100_2.png) [@jtp](https://discourse.jupyter.org/u/jtp)\
**Post date:** [July 13, 2021, 12:03pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/8 "2021-07-13T12:03:48Z")

</div>

> [@krassowski](#):
>
> I would advise to try creating a fresh virtual environment

Yes that would be a good way to make sure everything is correctly installed.

Although the dependencies listed in the top comment look good at first glance.

---

<div class="post-metadata">

**Author:** ![matt](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/matt/32/4710_2.png) [@matt](https://discourse.jupyter.org/u/matt)\
**Post date:** [July 13, 2021, 9:04pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/9 "2021-07-13T21:04:49Z")

</div>

I do not run it in a conda or any virtual env. I am running inside a docker image with just the packages I have listed installed. i updated everything to latest and still see the debugger missing.

In addition to the control error. i am also seeing `[W 2021-07-13 20:52:53.628 LabApp] Could not determine jupyterlab build status without nodejs` Is nodejs required?

```auto
Package Version Location
---------------------- ------------ ---------------------------------------
anyio 3.2.1
appmode 0.8.0
argon2-cffi 20.1.0
async-generator 1.10
attrs 21.2.0
Babel 2.9.1
backcall 0.2.0
beautifulsoup4 4.9.3
bleach 3.3.0
certifi 2021.5.30
cffi 1.14.6
charset-normalizer 2.0.1
cron-descriptor 1.2.24
cryptography 3.4.7
cycler 0.10.0
debugpy 1.3.0
decorator 5.0.9
defusedxml 0.7.1
Deprecated 1.2.12
entrypoints 0.3
idna 3.2
ipykernel 6.0.1
ipython 7.25.0
ipython-genutils 0.2.0
ipyvue 1.5.0
ipyvuetify 1.8.0
ipywidgets 7.6.3
jedi 0.18.0
Jinja2 3.0.1
json5 0.9.6
jsonschema 3.2.0
jupyter-client 6.1.12
jupyter-core 4.7.1
jupyter-server 1.9.0
jupyterlab 3.0.16
jupyterlab-pygments 0.1.2
jupyterlab-server 2.6.1
jupyterlab-widgets 1.0.0
kiwisolver 1.3.1
Mako 1.1.4
MarkupSafe 2.0.1
matplotlib 3.4.2
matplotlib-inline 0.1.2
mistune 0.8.4
nbclassic 0.3.1
nbclient 0.5.3
nbconvert 6.1.0
nbformat 5.1.3
nest-asyncio 1.5.1
notebook 6.4.0
numpy 1.21.0
p2j 1.3.2
packaging 21.0
pandas 1.3.0
pandocfilters 1.4.3
parsedatetime 2.6
parso 0.8.2
pexpect 4.8.0
pickleshare 0.7.5
Pillow 8.3.1
pip 21.1.2
plotly 5.1.0
prometheus-client 0.11.0
prompt-toolkit 3.0.19
ptyprocess 0.7.0
pycparser 2.20
Pygments 2.9.0
pyOpenSSL 20.0.1
pyparsing 2.4.7
pyrsistent 0.18.0
python-dateutil 2.8.1
pytz 2021.1
pyzmq 22.1.0
recurrent 0.4.0
requests 2.26.0
requests-unixsocket 0.2.0
scipy 1.7.0
Send2Trash 1.7.1
setuptools 57.1.0
six 1.16.0
sniffio 1.2.0
soupsieve 2.2.1
tenacity 8.0.1
terminado 0.10.1
testpath 0.5.0
tornado 6.1
traitlets 5.0.5
tzlocal 2.1
urllib3 1.26.6
wcwidth 0.2.5
webencodings 0.5.1
websocket-client 1.1.0
wheel 0.36.2
widgetsnbextension 3.5.1
wrapt 1.12.1

```

---

<div class="post-metadata">

**Author:** ![krassowski](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/krassowski/32/1685_2.png) [@krassowski](https://discourse.jupyter.org/u/krassowski)\
**Post date:** [July 14, 2021, 1:58pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/10 "2021-07-14T13:58:07Z")

</div>

No, Node.js is not required. It works for me with `jupyter/datascience-notebook`. Here is my pip list:

```auto
Package Version
----------------------------- -------------------
alembic 1.6.5
altair 4.1.0
anyio 3.2.1
appdirs 1.4.4
argon2-cffi 20.1.0
async-generator 1.10
attrs 21.2.0
Babel 2.9.1
backcall 0.2.0
backports.functools-lru-cache 1.6.4
beautifulsoup4 4.9.3
bleach 3.3.0
blinker 1.4
bokeh 2.3.3
Bottleneck 1.3.2
brotlipy 0.7.0
cached-property 1.5.2
certifi 2021.5.30
certipy 0.1.3
cffi 1.14.5
chardet 4.0.0
click 8.0.1
cloudpickle 1.6.0
conda 4.10.2
conda-package-handling 1.7.3
cryptography 3.4.7
cycler 0.10.0
Cython 0.29.23
cytoolz 0.11.0
dask 2021.6.2
debugpy 1.3.0
decorator 5.0.9
defusedxml 0.7.1
dill 0.3.4
distributed 2021.6.2
entrypoints 0.3
fsspec 2021.6.1
gmpy2 2.1.0b5
greenlet 1.1.0
h5py 3.3.0
HeapDict 1.0.1
idna 2.10
imagecodecs 2021.6.8
imageio 2.9.0
importlib-metadata 4.6.1
ipykernel 6.0.1
ipympl 0.7.0
ipython 7.25.0
ipython-genutils 0.2.0
ipywidgets 7.6.3
jedi 0.18.0
Jinja2 3.0.1
joblib 1.0.1
json5 0.9.5
jsonschema 3.2.0
jupyter-client 6.1.12
jupyter-core 4.7.1
jupyter-server 1.9.0
jupyter-telemetry 0.1.0
jupyterhub 1.4.1
jupyterlab 3.0.16
jupyterlab-pygments 0.1.2
jupyterlab-server 2.6.0
jupyterlab-widgets 1.0.0
kiwisolver 1.3.1
llvmlite 0.36.0
locket 0.2.0
Mako 1.1.4
mamba 0.14.1
MarkupSafe 2.0.1
matplotlib 3.4.2
matplotlib-inline 0.1.2
mistune 0.8.4
mock 4.0.3
mpmath 1.2.1
msgpack 1.0.2
nbclassic 0.3.1
nbclient 0.5.3
nbconvert 6.1.0
nbformat 5.1.3
nest-asyncio 1.5.1
networkx 2.3
notebook 6.4.0
numba 0.53.1
numexpr 2.7.3
numpy 1.21.0
oauthlib 3.1.1
olefile 0.46
packaging 21.0
pamela 1.0.0
pandas 1.3.0
pandocfilters 1.4.2
parso 0.8.2
partd 1.2.0
patsy 0.5.1
pexpect 4.8.0
pickleshare 0.7.5
Pillow 8.3.1
pip 21.1.3
pooch 1.4.0
prometheus-client 0.11.0
prompt-toolkit 3.0.19
protobuf 3.17.2
psutil 5.8.0
ptyprocess 0.7.0
pycosat 0.6.3
pycparser 2.20
pycurl 7.43.0.6
Pygments 2.9.0
PyJWT 2.1.0
pyOpenSSL 20.0.1
pyparsing 2.4.7
pyrsistent 0.17.3
PySocks 1.7.1
python-dateutil 2.8.1
python-editor 1.0.4
python-json-logger 2.0.1
pytz 2021.1
PyWavelets 1.1.1
PyYAML 5.4.1
pyzmq 22.1.0
requests 2.25.1
requests-unixsocket 0.2.0
rpy2 3.4.5
ruamel-yaml-conda 0.15.80
ruamel.yaml 0.17.10
ruamel.yaml.clib 0.2.2
scikit-image 0.18.2
scikit-learn 0.24.2
scipy 1.7.0
seaborn 0.11.1
Send2Trash 1.7.1
setuptools 49.6.0.post20210108
simplegeneric 0.8.1
six 1.16.0
sniffio 1.2.0
sortedcontainers 2.4.0
soupsieve 2.0.1
SQLAlchemy 1.4.20
statsmodels 0.12.2
sympy 1.8
tables 3.6.1
tblib 1.7.0
terminado 0.10.1
testpath 0.5.0
threadpoolctl 2.1.0
tifffile 2021.7.2
toolz 0.11.1
tornado 6.1
tqdm 4.61.2
traitlets 5.0.5
typing-extensions 3.10.0.0
tzlocal 2.1
urllib3 1.26.6
wcwidth 0.2.5
webencodings 0.5.1
websocket-client 0.57.0
wheel 0.36.2
widgetsnbextension 3.5.1
xlrd 2.0.1
zict 2.0.0
zipp 3.5.0

```

---

<div class="post-metadata">

**Author:** ![krassowski](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/krassowski/32/1685_2.png) [@krassowski](https://discourse.jupyter.org/u/krassowski)\
**Post date:** [July 14, 2021, 2:00pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/11 "2021-07-14T14:00:20Z")

</div>

Just to be clear by `jupyter/datascience-notebook` I mean: [docker-stacks/datascience-notebook at master · jupyter/docker-stacks · GitHub](https://github.com/jupyter/docker-stacks/tree/master/datascience-notebook)

---

<div class="post-metadata">

**Author:** ![krassowski](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/krassowski/32/1685_2.png) [@krassowski](https://discourse.jupyter.org/u/krassowski)\
**Post date:** [July 30, 2021, 1:41pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/12 "2021-07-30T13:41:24Z")

</div>

There was another report of this issue here: [User Input guard/popup prevents further execution after stopping execution and kernel restarts · Issue #10732 · jupyterlab/jupyterlab · GitHub](https://github.com/jupyterlab/jupyterlab/issues/10732#issuecomment-889860127)

---

<div class="post-metadata">

**Author:** ![Anton\_Akhmerov](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/anton_akhmerov/32/945_2.png) [@Anton\_Akhmerov](https://discourse.jupyter.org/u/Anton_Akhmerov)\
**Post date:** [July 30, 2021, 2:08pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/13 "2021-07-30T14:08:34Z")

</div>

Wohoo, removing all kernelspecs and reinstalling them again worked!

---

<div class="post-metadata">

**Author:** ![Anton\_Akhmerov](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/anton_akhmerov/32/945_2.png) [@Anton\_Akhmerov](https://discourse.jupyter.org/u/Anton_Akhmerov)\
**Post date:** [July 30, 2021, 2:26pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/14 "2021-07-30T14:26:27Z")

</div>

@matt: try `jupyter kernelspec list`, then look in the `kernel.json`. It must have

```json
 "metadata": {
  "debugger": true
 }

```

in order for the debugger to be active, if I get things right.

---

<div class="post-metadata">

**Author:** ![matt](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/matt/32/4710_2.png) [@matt](https://discourse.jupyter.org/u/matt)\
**Post date:** [July 30, 2021, 5:00pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/15 "2021-07-30T17:00:11Z")

</div>

@Anton_Akhmerov  
My kernel.json has debugger set to true but it is still missing .If I remove it, how do I add it back?

I have upgraded to lab 3.1.1 and ipykernel 6.0.3. I no longer see the `[W 00:49:42.417 NotebookApp] No such channel: 'control'` error from before

THanks!  
 ![image](https://canada1.discourse-cdn.com/flex031/uploads/jupyter/original/2X/8/84b6683277b67c936a3b66214d9513b154ea3a19.png)

---

<div class="post-metadata">

**Author:** ![Anton\_Akhmerov](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/anton_akhmerov/32/945_2.png) [@Anton\_Akhmerov](https://discourse.jupyter.org/u/Anton_Akhmerov)\
**Post date:** [July 30, 2021, 5:54pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/16 "2021-07-30T17:54:33Z")

</div>

Installing is done via `python -m ipykernel install --user --name python --display-name "Python 3"`

---

<div class="post-metadata">

**Author:** ![matt](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/matt/32/4710_2.png) [@matt](https://discourse.jupyter.org/u/matt)\
**Post date:** [July 30, 2021, 6:24pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/17 "2021-07-30T18:24:38Z")

</div>

Thanks for the help. Still no luck.

Checking logs when I switch kernels I do still get [W 2021-07-30 18:22:03.947 ServerApp] No such channel: ‘control’ error message. I believe this is the root of my problem. I think ill post a separate thread on this error and see if anyone has thoughts on that and will circle back to this thread if it is resolved. Thanks again!

Matt

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<div class="post-metadata">

**Author:** ![shaimarvinblue](https://yyz1.discourse-cdn.com/flex031/user_avatar/discourse.jupyter.org/shaimarvinblue/32/11657_2.png) [@shaimarvinblue](https://discourse.jupyter.org/u/shaimarvinblue)\
**Post date:** [November 20, 2023, 12:39pm UTC](https://discourse.jupyter.org/t/missing-debugger-option/9851/18 "2023-11-20T12:39:58Z")

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this worked for me when variables didn’t load in vscode and Jupyter lab debugger was grayed out