Provokes the same Gtk "object drawn out of bounds" errors we've seen in the past, so if it could be fixed then, presumably a new fix exists in this instance (it's never been more than a concerning looking warning in the logs anyhow).
I have no idea what the underlying issue actually is, besides that it triggers with older version of PyQt4. I can see it on my Debian7 VM, I don't think I can on Debian 8. What version are you using Qt are you using?
Version 4.8.6, Debian 8.5. Pretty sure that's the most up to date version in the Debian 8 standard repo.