diff --git a/docu/mars-user-manual.lyx b/docu/mars-user-manual.lyx
index e9115f63..255e26b9 100644
--- a/docu/mars-user-manual.lyx
+++ b/docu/mars-user-manual.lyx
@@ -19248,6 +19248,10 @@ framecolor "black"
 backgroundcolor "none"
 status open
 
+\begin_layout Plain Layout
+Only useful for debugging.
+\end_layout
+
 \begin_layout Plain Layout
 
 \size scriptsize