diff --git a/include/maskfld.cpp b/include/maskfld.cpp
index ffed1beed..4caf7264a 100755
--- a/include/maskfld.cpp
+++ b/include/maskfld.cpp
@@ -3732,6 +3732,7 @@ bool TList_field::on_key(KEY key)
   if (key == K_SPACE)
   {
     get_window_data();
+    set_dirty();
     on_hit();
   }
   else