Drupal 12 compatibility: add ^12 to core_version_requirement and fix removed/changed APIs [#3629653]

Problem/Motivation

Drupal 12 is scheduled for GA in December 2026. The latest release of config_update (8.x-1.7) does not declare ^12 in core_version_requirement, so Composer cannot install it on Drupal 12.

Proposed resolution

Add ^12 to core_version_requirement and update code that breaks on Drupal 12 (removed or changed core APIs). The change touches 3 file(s), about 14 changed line(s).

The change is attached to this issue as a patch (generated against 8.x-1.7).

Remaining tasks

Review the merge request
Merge and tag a release that includes ^12

Needed by the YMCA Website Services (Open Y) distribution for Drupal 12.

Issue fork config_update-3629653

Show commands

Start within a Git clone of the project using the version control instructions.

Add & fetch this issue fork’s repository

Or, if you do not have SSH keys set up on git.drupalcode.org:

Add & fetch this issue fork’s repository

3629653-drupal-12-compatibility-2-0-x changes, plain diff MR !22
Check out this branch for the first time

Check out existing branch, if you already have it locally
3629653-drupal-12-compatibility compare
Check out this branch for the first time

Check out existing branch, if you already have it locally