Tested gparted-0.23.0-66.1.x86_64.rpm on openSUSE 20150924 (Tumbleweed) (x86_64) and it starts as expected from the desktop launcher, asking for root password via pkexec. So bug is FIXED for Tumbleweed as I see it. Installation on Leap Beta1 fails due to older libstdc++6 at the moment.