qt5 gtk theme

export QT_QPA_PLATFORMTHEME=qt5ct
echo QT_QPA_PLATFORMTHEME="qt5ct" >> /etc/environment
aptitude install qt5ct qt5-gtk2-platformtheme qt5-style-plugins -t sid
.config/qt5ct/qt5ct.conf:
...
[Appearance]
...
icon_theme=moblin
standard_dialogs=gtk3
style=gtk2
...