Any dock window that is added to a QMainWindow will stay on top of anything after being pulled out.

This is problematic when you try and minimize the application and when you want to use a dialog over this dock. When a new dialog is created, it is hidden behind the dock, despite its modality.

Example: Build then click the button. The input appears on top of the main widget as expected. Now pull out the dock widget and click again. It is now buried behind the floating dock and inaccessible.

Steps to reproduce with qtbase/examples/widgets/mainwindows/mainwindow:

• Launch example
• Undock a dock widget
• Choose "File/Load..."
• Note: dock is on top of file dialog