1. sphinx-version-warning: allows you to add a custom warning banner at the top of your documentation pages to communicate some important about this documentation: https://sphinx-version-warning.readthedocs.io

2. sphinx-notfound-page: is great to create a "Not found" (or 404) page to show when the reader hit a not found page: https://sphinx-notfound-page.readthedocs.io

3. sphinx-hoverxref: adds amazing tooltips on your cross-references that points to another page/section of the documentation including its content on the tooltip: https://sphinx-hoverxref.readthedocs.io

#python