how do I go about diagnosing a windowing problem that only happens under gnome shell?

[drago01]

On Fri, Feb 1, 2013 at 6:15 PM, Matthew Miller <mattdm at fedoraproject.org> wrote:
> Under Gnome in Fedora 18, returning from full screen in Squeak (including in
> the Scratch RPM I'm working on) results in an all-black nonresponsive
> window. Doesn't happen in fallback mode or in Xfce (even with compositing
> enabled). https://bugzilla.redhat.com/show_bug.cgi?id=906425
>
> How do I go about finding what's to blame and fixing it?

Is this an override redirect window? Or how does it fullscreen itself?
If it is the former does Alt-f2 "lg" and then

 Meta.disable_unredirect_for_screen(global.screen);

make it work?