White spaces in Kmail (dark themes)

Hi, After the recent updates of qt5-qtwebengine there are white spaces in the message window when using a Dark Theme. Another user has just reported this on kde.bugs with a screen shot https://bugs.kde.org/show_bug.cgi?id=379406 I don't know if it is a kmail or qtwebengine bug or even related to mesa/ nouveau saga. Kmail 5.4.3 Plasma 5.9.5 Frameworks 5.33 Mesa-dri-drivers-13.0.4-3.fc25.nouvlock Colin -- Fedora 25 (Twenty Five) Registered Linux user number #342953