- Open My Computer, browse to some folder with contents, e.g. C:\ReactOS
- Open Task Manager, switch to Processes tab and select a process
- Minimize Task Manager
- Double-click Task Manager tray icon to restore
- Select the explorer window by clicking into its ListView area. Notice the title bar stays at Inactive state
- Select a file or folder and press Del. Notice you get Task Manager's End Process dialog, because keyboard focus has not changed correctly
- Focus switching by clicking on a window is generally broken from now on. Switching using the task bar buttons works as expected.