Patch didn't make it in time for 5.3.0, will be part of 5.3.1. Otherwise context menus will be rendered quite broken: http://bugsfiles.kde.org/attachment.cgi?id=86801 See also: https://bugs.kde.org/show_bug.cgi?id=335289
Patch added. Thanks. https://git.overlays.gentoo.org/gitweb/?p=proj/qt.git;a=commit;h=df6eab209d70041be2127f15e9979798ec1214ca