As a result of using QWidget::setVisible to show the child widgets we would end up also setting ExplicitShowHide. This is not in line with the intent of ExplicitShowHide, which is to flag a widget as explicitly shown/hidden by the developer, which in turn prevents Qt Widgets from toggling WState_Hidden when the widget is reparented. By using QWidgetPrivate::setVisible instead, we can show the child without setting ExplicitShowHide. As side effect of this is that we no longer reset WA_WState_Hidden from QWidgetWindowPrivate::setVisible(). This is an issue when the setVisible call comes as a result of destroying the QWidgetWindow, as that is an implicit hide, and should not result in the widget having WA_WState_Hidden. QWidget handles this case in hideChildren by not calling QWidgetPrivate::setVisible -- instead doing its own reset of WA_WState_Visible. We don't want to untangle this just yet, so as a workaround we detect that the widget is already !isVisible(), thanks to hideChildren having hidden it, and then skip the call to QWidgetPrivate::setVisible that results from QWindow::destroy(). Task-number: QTBUG-121398 Pick-to: 6.7 Change-Id: Ib5b4d9c84f0569124c5f3ca2169cabff18934e2d Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org> Reviewed-by: Axel Spoerl <axel.spoerl@qt.io>