Block Comment Not Working in Jupyter Notebook

JupyterLab
1

Using the following versions of packages on my Ubuntu 20.04 inside a venv.

IPython          : 8.12.3
ipykernel        : 6.29.4
ipywidgets       : 8.1.3
jupyter_client   : 8.6.2
jupyter_core     : 5.7.2
jupyter_server   : 2.14.1
jupyterlab       : 4.2.3
nbclient         : 0.10.0
nbconvert        : 7.16.4
nbformat         : 5.10.4
notebook         : 7.2.1
qtconsole        : 5.5.2
traitlets        : 5.14.3

I thought Ctrl+/ is meant for block comment or uncomment, I have used it previously as well. But seems suddenly it stopped working, as in it has no effect.

A few more relevant information

  • Keyboard layout: English (US), the built in keyboard of the Laptop
  • Tested the keys themselves, as in Ctrl and / separately, they have the intended effects for other purposes, such as Ctrl+C for copying. So does not appear like a hardware issue.
3

Strictly Ctrl + / this is a multi-line comment. This does not matter unless you reassigned it to block-comment, which is not implemented in some languages like Python.