diff --git a/css-text-4/Overview.bs b/css-text-4/Overview.bs
index 10eac1cdd20..c10c9da3f5a 100644
--- a/css-text-4/Overview.bs
+++ b/css-text-4/Overview.bs
@@ -8039,6 +8039,9 @@ Automatic Contextual Spacing: the 'text-autospace' property</h3>
 			The specified spacing is automatically inserted
 			if there are no space characters of any kind ([=Unicode general category=] <code>Z</code>) already there.
 
+			If neither ''text-autospace/insert'' nor ''text-autospace/replace'' are specified,
+			the behavior is the same as ''text-autospace/insert''.
+
 		<dt><dfn>replace</dfn>
 		<dd>
 			The specified spacing is automatically inserted