OK, thanks all for your investigations. This all sounds very promising. So, to summarize (please correct me if I am wrong): - There was a bug in the Qt libs. - We now have a fix as a patch on top of our Qt libs build. - That patch was also sent upstream, but of course it will take a while until the fixed version trickles down to us again. Is there anything left for the installer to do? I don't see anything.