Add a missing break statement.
diff --git a/vncviewer/Viewport.cxx b/vncviewer/Viewport.cxx
index e6183bc..4bd0758 100644
--- a/vncviewer/Viewport.cxx
+++ b/vncviewer/Viewport.cxx
@@ -869,6 +869,7 @@
     break;
   case ID_MINIMIZE:
     window()->iconize();
+    break;
   case ID_RESIZE:
     if (window()->fullscreen_active())
       break;