Quick Designer's minimum width setting persists

1. Start Creator.
2. Try how far you can reduce the width of Creator's main window.
   You can make Creator about 250 pixels wide.
3. Open a QML file and switch to Design mode.
   Creator will grow to a width of about 1050 pixels. This makes sense because the Designer displays a lot of controls.
4. Go back to Edit mode.
5. Try how far you can reduce the width of Creator's main window.
   You can't. Creator still requires the whole width that was used for the Design mode.

After leaving the Design mode you should be able to make Creator smaller again.