参考 https://forum.kde.org/viewtopic.php?f=224&t=160993
pkexec env DISPLAY=$DISPLAY XAUTHORITY=$XAUTHORITY KDE_SESSION_VERSION=5 KDE_FULL_SESSION=true dolphin
pkexec env DISPLAY=$DISPLAY XAUTHORITY=$XAUTHORITY KDE_SESSION_VERSION=5 KDE_FULL_SESSION=true dolphin