Comment # 2 on bug 1013569 from Wolfgang Bauer

(In reply to Daniel Zeleny from comment #1)
> Fixed in QT 5.9.5: https://bugreports.qt.io/browse/QTBUG-59261 
> Will it be in Leap 15?

That patch is included in Leap 15.0's libqt5-qtbase package since about a
month:
https://build.opensuse.org/package/view_file/openSUSE:Leap:15.0/libqt5-qtbase/0001-Avoid-providing-bad-pixelDeltas-on-X11.patch?expand=1