diff --git a/en/08_Changelogs/5.4.0.md b/en/08_Changelogs/5.4.0.md
index 14b18557..81c5fe6d 100644
--- a/en/08_Changelogs/5.4.0.md
+++ b/en/08_Changelogs/5.4.0.md
@@ -189,6 +189,7 @@ The `SilverStripe\CMS\Model\SiteTree.DESCRIPTION` localisation key (along with t
 - [`LeftAndMain::Modals()`](api:SilverStripe\Admin\LeftAndMain::Modals()) has been deprecated. It will be removed without equivalent functionality to replace it.
 - [`ModalController::getController()`](api:SilverStripe\Admin\ModalController::getController()) has been deprecated. It will be removed without equivalent functionality to replace it.
 - [`ModalController::getName()`](api:SilverStripe\Admin\ModalController::getName()) has been deprecated. It will be removed without equivalent functionality to replace it.
+- [`FormField::validate()`](api:SilverStripe\Forms\FormField::validate()) will take zero arguments and return a ValidationResult object instead of a boolean in CMS 6.0.0.
 
 ## Bug fixes