diff --git a/etc/NEWS b/etc/NEWS
index 592b343b19e..3f91ef13536 100644
--- a/etc/NEWS
+++ b/etc/NEWS
@@ -4352,6 +4352,9 @@ buffer.
 If non-nil, that says to preserve the window's current margin, fringe,
 and scroll-bar settings.
 
++++
+*** The new function `window-split-tree' returns a frame's window split tree.
+
 +++
 ** Customizable fringe bitmaps