I'm a little bit worried... maybe this patch to Glade is going to
work fine... the part in glade_widget_dispose() that leaves old GtkObjects
such as adjustments and size-groups is a little sensitive (i.e. breaking
reference cycles is an important step when trying to balance out refcounts
at project close time... a painful exercise that often needs repeating).

However on a more global picture, how are we supposed to handle breaking
of circular object references with the new scheme ?

I think it might be wise to push GtkWidget::destroy signal back to the 
GObject level instead of absorbing it into GtkWidget
(people can always chose to call g_object_run_dispose(), but that still
doesn't provide any notifications to the objects which should unref the
dying object at dispose time).

does g_object_weak_ref() solve the problem?

I committed this in offscreen-gtk3 branch and it doesn't seem to cause any problems, yet.

Comment on attachment 171172 [details] [review]
patch

commit cbc454d050a79e8ff863b236e635997672cbd944

This problem has been fixed in the development version. The fix will be available in the next major software release. Thank you for your bug report.