diff --git a/src/plugins/platforms/xcb/qxcbwindow.cpp b/src/plugins/platforms/xcb/qxcbwindow.cpp
index 00bca0def9..7b1072deb3 100644
--- a/src/plugins/platforms/xcb/qxcbwindow.cpp
+++ b/src/plugins/platforms/xcb/qxcbwindow.cpp
@@ -1846,7 +1846,7 @@ void QXcbWindow::handleUnmapNotifyEvent(const xcb_unmap_notify_event_t *event)
     if (event->window == m_window) {
         m_mapped = false;
         QWindowSystemInterface::handleExposeEvent(window(), QRegion());
-        if (!m_isWmManagedWindow) {
+        if (!m_isWmManagedWindow || parent()) {
             m_wmStateValid = true;
             handleDeferredTasks();
         }