(In reply to comment #34)
> (In reply to comment #33)
> > (which AFAIK is normal, but didn't happen before).
> 
> Yes, that's normal and not related to this problem.
> 
> Note that the 'Attempted to destroy previously destroyed buffer.' messages
> would appear in the Xorg / LightDM log files, not in the terminal where you
> run the application.

Yes. Sorry if I was not clear, I grep'd through Xorg.*.log, and was not there.
Anyway, please allow someone else to confirm that the patch works.