diff --git a/CHANGELOG.txt b/CHANGELOG.txt
index 3824763407..76b1bf0aed 100644
--- a/CHANGELOG.txt
+++ b/CHANGELOG.txt
@@ -23,6 +23,7 @@ Changelog
  * Fix: Remove extra padding for headers with breadcrumbs on mobile viewport (Steven Steinwand)
  * Fix: Ensure the upgrade notification request for the latest release, which can be disabled via the `WAGTAIL_ENABLE_UPDATE_CHECK` sends the referrer origin with `strict-origin-when-cross-origin` (Karl Hobley)
  * Fix: Ensure radio buttons / checkboxes display vertically under Django 4.0 (Matt Westcott)
+ * Fix: Ensure that custom document or image models support custom tag models (Matt Westcott)
 
 
 3.0 (16.05.2022)
diff --git a/docs/releases/4.0.md b/docs/releases/4.0.md
index 9bb3b5672e..4a207bc5fb 100644
--- a/docs/releases/4.0.md
+++ b/docs/releases/4.0.md
@@ -33,6 +33,7 @@ depth: 1
  * Replace `PageRevision` with generic `Revision` model (Sage Abdullah)
  * Ensure the upgrade notification request for the latest release, which can be disabled via the `WAGTAIL_ENABLE_UPDATE_CHECK` sends the referrer origin with `strict-origin-when-cross-origin` (Karl Hobley)
  * Ensure radio buttons / checkboxes display vertically under Django 4.0 (Matt Westcott)
+ * Ensure that custom document or image models support custom tag models (Matt Westcott)
 
 
 ## Upgrade considerations