Config Filter

Use config transformation instead

This module was the go-to API before Drupal 8.8. However, in Drupal 8.8 a new API was added to core. Modules may not have been updated immediately so this module remained supported to allow the transition. This module will become unsupported in Drupal 12.

Config Filter is not compatible with PHP constants and enums in yaml files outside of the sync directory.

Writing tests for modules using Config FIlter or the core API

Config Filter comes with test traits that can be used to write tests for modules with config filter plugins and that want to refactor to use the new core API. The tests written with the config filter test traits will work without change when the module uses the core API. You should adopt these traits to your module.

How to stop using Config Filter

Urge maintainers of modules depending on config filter to refactor using the core API. The test traits of config filter can be used to first refactor the tests to use the traits, have tests pass, then refactor the module while keeping the tests still passing, updating to 2.x of config filter, then adopt the traits.

This module will not be supported in Drupal 12. Not because it couldn't be made to work with Drupal 12, but because it is time to use the API added to Drupal 8.8.