Drupal 10 -> 11 Upgrades

Install the Drupal Upgrade Status module on your Drupal 10 site.

1. Run on a pantheon multidev to get an accurate hosting environment status.

Review status /admin/reports/upgrade-status

Update Drupal core to 10.3 (or the latest version of 10 at the time of upgrade)

Update your version of PHP to at least 8.3

Make sure your site is running on it

Run composer why-not php 8.3 to see if any packages need updates (only works if PHP 8.3 is a composer dependency in your composer.json). I recommend including it as a dev dependency and removing it after an upgrade.

Deprecated modules

1. Actions UI, Activity Tracker, Book, Forum, Layout Builder Expose All Field Blocks, Statistics, Tour

Remove uninstalled incompatible modules and themes

Update contrib modules to their compatible latest versions and test the functionality. Some modules we may need to help review and release a Drupal 11 version.

Scan custom modules for deprecations and fix with Rector or manually

If the site is on Pantheon, update pantheon.yml with the correct version of PHP

Push your changes to the multidev, test the functionality, and ask PM and the client to test

Merge changes with Dev branch, and retest. Move them to test and test with the client

Schedule the deployment, make the backup, and deploy to live