diff --git a/docs/grub.texi b/docs/grub.texi
index c25ab7a5f..08d699d49 100644
--- a/docs/grub.texi
+++ b/docs/grub.texi
@@ -5717,7 +5717,8 @@ the GRUB command line, edit menu entries, and execute any menu entry.  If
 @samp{superusers} is set, then use of the command line and editing of menu
 entries are automatically restricted to superusers. Setting @samp{superusers}
 to empty string effectively disables both access to CLI and editing of menu
-entries.
+entries. Note: The environment variable needs to be exported to also affect
+the section defined by the @samp{submenu} command (@pxref{submenu}).
 
 Other users may be allowed to execute specific menu entries by giving a list of
 usernames (as above) using the @option{--users} option to the