Bug#787680: Qt5: Applications disappear or crash when screen is switched

[Ralf Jung <post@ralfj.de>]

For the record, there's two more related upstream issues:
<https://bugreports.qt.io/browse/QTBUG-42985>
<https://bugreports.qt.io/browse/QTBUG-47041>

With Qt 5.5, there was lots of work on this issue. It did not get fixed,
though - at least on my system. I came up with a patch against Qt 5.5
that fixes the problem here, it's linked from the 2nd bugreport above
and currently under review at the Qt project.

There's hope at the horizon :D (at least once Qt 5.5 lands in Debian ;-).

Kind regards,
Ralf