The upgrade path from Drupal 9 to Drupal 10 depends on the modules and themes you have installed and on the custom ones your team have developed.
Following the official guide of this upgrade will hopefully take you through the process and resolve all the issues you might encounter.
In our case we had a custom built theme started on Drupal 9 and it did follow all the latest standards and recommendations of the time. After the migration process completed successfully we kept seeing warnings in our admin status reports about the stable theme being deprecated. We could not find a straightforward guide to handle this issue and hence after a bit of research and resolution we are writing this guide. We have taken a few ideas from this change record about the stable theme being removed from core.
Below is a step by step guide on how to fully migrate your custom coded theme from Drupal 9 to Drupal 10 and removing all warnings from the status report.
Congratulations on your proper upgrade to Drupal 10 and enjoy the new features!
Founder of SOFTKUBE, lead developer, and getting things done addict. Passionate about open source, user interface design, business development, and the tech world.
A small team of experts developing simple, usable, and high-quality web solutions. We blog about business, entrepreneurship, web development, and technology.
Custom Theme Migration from Drupal 9 to Drupal 10
Business Cheat Sheets CLI Design Development Downloads Drupal Email Google Apps HID Keyboards Multilingualism Open Source Philosophy PHP Pointing Devices Productivity Quotes Science Security SEO Technology Thoughts Windows Zend Framework