diff --git a/vncviewer/DesktopWindow.cxx b/vncviewer/DesktopWindow.cxx
index f63b16e..7a5b4c3 100644
--- a/vncviewer/DesktopWindow.cxx
+++ b/vncviewer/DesktopWindow.cxx
@@ -301,5 +301,10 @@
     self->grabKeyboard();
   else
     self->ungrabKeyboard();
+
+  if (fullScreen && !self->fullscreen_active())
+    self->fullscreen();
+  else if (!fullScreen && self->fullscreen_active())
+    self->fullscreen_off();
 #endif
 }