silverstripe-framework/docs/en/04_Changelogs/4.2.1.md

4.2.1

Notable changes

Fix #7971 introduces a subtle change of behaviour to how Config settings are prioritised. In SilverStripe 4 there was a change where Extension objects took the highest importance when determining Config values; this was deemed to be unexpected and unintuitive as well as making it cumbersome and difficult for developers to override module defaults defined in Extensions. This change reverts behaviour to that of SilverStripe 3 where Extension instances are of lowest importance and are used only to set a default value. If you rely on your Extension or module providing an overriding config value, please move this to yaml.