diff --git a/src/cmd/ksh93/COMPATIBILITY b/src/cmd/ksh93/COMPATIBILITY
index 403795ebc..5db2558a3 100644
--- a/src/cmd/ksh93/COMPATIBILITY
+++ b/src/cmd/ksh93/COMPATIBILITY
@@ -107,6 +107,10 @@ For more details, see the NEWS file and for complete details, see the git log.
 20.	If the HOME variable is unset, the bare tilde ~ now expands to the
 	current user's system home directory instead of merely the username.
 
+21.	On Windows/Cygwin, globbing is no longer case-insensitive by default.
+	Turning on the new --globcasedetect shell option restores
+	case-insensitive globbing for case-insensitive file systems.
+
 ____________________________________________________________________________
 
 		KSH-93 VS. KSH-88