fix crash when changing to default session

--this was a rare crash when changing to default
session from the alternative one through the context
menu of the Tasks plasmoid there was a crash sometimes

app/dockview.cpp

@@ -130,6 +130,9 @@ DockView::DockView(Plasma::Corona *corona, QScreen *targetScreen, bool dockWindo
 
 DockView::~DockView()
 {
+    disconnect(corona(), &Plasma::Corona::availableScreenRectChanged, this, &DockView::availableScreenRectChanged);
+
+    m_inDelete = true;
     m_screenSyncTimer.stop();
 
     qDebug() << "dock view deleting...";
@@ -169,10 +172,9 @@ void DockView::init()
     connect(this, &QQuickWindow::widthChanged, this, &DockView::updateAbsDockGeometry);
     connect(this, &QQuickWindow::heightChanged, this, &DockView::heightChanged);
     connect(this, &QQuickWindow::heightChanged, this, &DockView::updateAbsDockGeometry);
-    connect(corona(), &Plasma::Corona::availableScreenRectChanged, this, [&]() {
+
-        if (formFactor() == Plasma::Types::Vertical)
+    connect(corona(), &Plasma::Corona::availableScreenRectChanged, this, &DockView::availableScreenRectChanged);
-            syncGeometry();
+
-    });
     connect(this, &DockView::behaveAsPlasmaPanelChanged, this, &DockView::syncGeometry);
     connect(this, &DockView::drawShadowsChanged, this, &DockView::syncGeometry);
     connect(this, &DockView::maxLengthChanged, this, &DockView::syncGeometry);
@@ -219,6 +221,12 @@ void DockView::init()
     qDebug() << "SOURCE:" << source();
 }
 
+void DockView::availableScreenRectChanged()
+{
+    if (formFactor() == Plasma::Types::Vertical)
+        syncGeometry();
+}
+
 void DockView::setupWaylandIntegration()
 {
     using namespace KWayland::Client;

app/dockview.h

@@ -232,6 +232,7 @@ signals:
     void absGeometryChanged(const QRect &geometry);
 
 private slots:
+    void availableScreenRectChanged();
     void menuAboutToHide();
     void statusChanged(Plasma::Types::ItemStatus);
     void screenChanged(QScreen *screen);
@@ -258,6 +259,7 @@ private:
     bool m_dockWinBehavior{false};
     bool m_drawShadows{true};
     bool m_drawEffects{false};
+    bool m_inDelete{false};
     bool m_onPrimary{true};
     int m_dockTransparency{100};
     int m_maxThickness{24};