1 files changed, 1 insertions, 0 deletions
diff --git a/src/dispextern.h b/src/dispextern.h
index be6c2fbecbb..1957e3b7e7e 100644
--- a/src/dispextern.h
+++ b/src/dispextern.h
@@ -101,6 +101,7 @@ struct frame_glyphs
 
     /* When representing a desired frame,
          enable[n] == 0 means that line n is same as current frame.
+	 Between updates, all lines should be disabled.
        When representing current frame contents,
          enable[n] == 0 means that line n is blank.  */
     char *enable;