124891: <SidebarDockingWindow::GetFocus()> - check, if sidebar controller is…

124891: <SidebarDockingWindow::GetFocus()> - check, if sidebar controller is available before accessing it.

sfx2/source/sidebar/SidebarDockingWindow.cxx

@@ -84,7 +84,10 @@ void SidebarDockingWindow::DoDispose (void)
 
 void SidebarDockingWindow::GetFocus()
 {
-    mpSidebarController->GetFocusManager().GrabFocus();
+    if (mpSidebarController.is())
+    {
+        mpSidebarController->GetFocusManager().GrabFocus();
+    }
 }