10 Essential Jupyter Notebook Extensions for Data Scientists
spellchecker

Also simple, yet useful, is the spellchecker. This extension is especially useful if you are sharing your notebook, pushing it to GitHub, or displaying it to stakeholders. You will want to make sure you have correctly spelled your words in your markdown cells. You will not see misspelled words show up in your displayed markdown, but only in your edit. This feature is beneficial so that if you do have some words that you disagree on with the spellchecker, like Jupyter Notebook (is not actually Jupiter Notebook), you can still display it without a distracting, red, highlighted text.

Spellcheck example. Screenshot by Author [9].

Code Font Size

If you want to change the code font size, this extension allows you to do that. When sharing and collaborating, especially sharing your screen, this feature can prove to be beneficial so that your code is easier to view.

datestamper

This extension allows you to paste your current date and time into your cell. I recommend saving it as a markdown so that the formatting does not run as code with hard-to-see formatting. If you want to keep track of when you started a process that involved different cells and functions, this extension can be useful (on top of the popular tqdm library).

Scratchpad

This extension is incredibly useful. You can use your scratchpad as seen below, by selection Ctrl-B on your keyboard. You can modify the current code that can work off the same kernel as well. It is also useful for viewing side-by-side code and comments if you need to compare them within your notebook.

Scratchpad example. Screenshot by Author [10].

Skip-Traceback

This unique extension allows you to ignore some of the duplicate or long error messages you see in your Jupyter Notebook cells. It works similarly to the Collapsible Headings and Codefolding. In the screenshot below, you can see how the main part of the error is still there on the right, but reduces the duplicate error information that can sometimes cause a headache and overwhelm you from fixing that same error.
['Matt Przybyla']
['Machine Learning', 'Technology', 'Education', 'Towards Data Science', 'Data Science']