No, I didn't check the code. I read the code looking for the answer to the original question, but couldn't find anything that was an answer for it. I'm not saying the answer isn't buried in there, but for a Gtk newbie (like myself), there didn't seem to be anything relevant, aside from the problem of digging through the various versions of the site looking for one without broken links.
The links in your first post were more helpful. ;^)
When your only tool is a hammer, all problems look like your thumb.