[12.x] [Meta] Tasks to remove Migrate Drupal UI module

Problem/Motivation

Track the steps needed to remove extension Migrate Drupal UI from core to contrib. See Remove a core module and move it to a contributed project → of the deprecation policy.

The removal of extension Migrate Drupal UI was approved in 📌 [Policy] Migrate Drupal and Migrate Drupal UI after Drupal 7 EOL Fixed .

Migrate Drupal UI is not being moved to contrib. The following step need to be updated accordingly.

Remaining tasks

1. Create a child issue, 'Remove Migrate Drupal UI from core'.
   • The change record for this issue should include a link to recommendations page, https://www.drupal.org/node/3223395#s-migrate-drupal-ui → . (For example, the CR for removing HAL → )
   • Tag this issue 'Needs release note.'
   • Remove the extension ;-).
   • Update Update path tests as needed. See Writing Automated Update Tests for Drupal 8 (or later) for details → .
   • Remove references from core/phpstan-baseline.neon.
   • Remove any spelling words specific to the extension from the dictionary
   • Add the extension to the relevant removed list, either DRUPAL_CORE_REMOVED_MODULE_LIST or DRUPAL_CORE_REMOVED_THEME_LIST, in system.install.
   • Check for references in @todo.
   • Handle migration tests.
     • In all the functional tests in migrate_drupal_ui make sure that Migrate Drupal UI is not installed. Migrate Drupal UI should also be removed from the methods getAvailablePaths() and moved to getMissingPaths() in the tests using those methods.
2. Deprecate the extension in the current minor development branch. If the next major branch is open, the extension can be removed via a separate patch (to avoid dependent patches), otherwise an issue should be opened to remove the extension once the next major branch is open.
3. Open an issue, 'Ensure that Migrate Drupal UI does not get special core treatment' in the packages.drupal.org issue queue → to ensure that the composer namespace for the contributed project matches the core one after removal. This is to allocate the drupal/migrate-drupal-ui Composer namespace to contrib extension rather than the core extension.
4. Manually test upgrading from the core extension to the contrib extension. There is an issue template → available for this.
5. Triage core issues for Migrate Drupal UI in the core queue and move either to the contrib project or the relevant core component. Restore the status to what it was before it was postponed. Also, is the issue moved to contrib, then move any change record.
6. Move all core documentation for Migrate Drupal UI to the contrib project. Make issues in the contrib project to update or add links to the documentation on the project page.
7. When the issue in https://www.drupal.org/project/project_composer → is Fixed update the documentation with the new Composer command.

Release notes snippet