Double click on "In main window (default)" and core dumped

[krzotr]

Tested on Fedora 23 i686.

How to reproduce?

1. Go to View -> Preferences -> Map -> Position
2. Make sure "In separate window" is default value
3. Click on "In main window (default)"
4. Once again click "In main window (default)"
5. Click "In separate window"
6. core dumped

         Gtk:ERROR:gtkcontainer.c:3835:gtk_container_propagate_draw: assertion failed:     (_gtk_widget_get_parent (child) == GTK_WIDGET (container))
         Interrupt (core dumped)