Update OneNote Class Notebook Add-in for Desktop by December 31

On December 31, 2022, Microsoft will disable the toolbar user-interface for OneNote Class Notebook add-in for desktop version 3.3 or older. If you are using this add-in, you must upgrade to the latest version, which is available for download at https://www.microsoft.com/download/details.aspx?id=51934.

To learn more about this, visit https://techcommunity.microsoft.com/t5/education-blog/updating-your-class-notebook-addin-for-onenote-desktop-to-the/ba-p/3072108.