diff --git a/win/vncviewer/DesktopWindow.cxx b/win/vncviewer/DesktopWindow.cxx
index d4bc3e7..f96c7e4 100644
--- a/win/vncviewer/DesktopWindow.cxx
+++ b/win/vncviewer/DesktopWindow.cxx
@@ -301,6 +301,8 @@
 void DesktopWindow::setShowToolbar(bool st)
 {
   showToolbar = st;
+  if (fullscreenActive) return;
+
   RECT r;
   GetWindowRect(handle, &r);
   bool maximized = GetWindowLong(handle, GWL_STYLE) & WS_MAXIMIZE;