diff --git a/UPGRADING.md b/UPGRADING.md
index 0184171ca0d..2c687b6ef55 100644
--- a/UPGRADING.md
+++ b/UPGRADING.md
@@ -8,6 +8,14 @@ The format of this change log follows the advice given at [Keep a CHANGELOG](htt
 
 ## 5.1.1+
 
+### core
+
+#### Added
+
+- There is a new Behat `toast_message` named selector to more easily assert the presence of Toast messages on the page
+
+  For more information see [MDL-87443](https://tracker.moodle.org/browse/MDL-87443)
+
 ### core_question
 
 #### Fixed
diff --git a/public/lib/UPGRADING.md b/public/lib/UPGRADING.md
index 4fa833af02c..37907974952 100644
--- a/public/lib/UPGRADING.md
+++ b/public/lib/UPGRADING.md
@@ -1,5 +1,13 @@
 # core (subsystem) Upgrade notes
 
+## 5.1.1+
+
+### Added
+
+- There is a new Behat `toast_message` named selector to more easily assert the presence of Toast messages on the page
+
+  For more information see [MDL-87443](https://tracker.moodle.org/browse/MDL-87443)
+
 ## 5.1.1
 
 ### Added