qtcurve from home:maxrd2:qt5:theme project
Select Your Operating System
Add repository and install manually
For openSUSE Leap 15.2 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:maxrd2:qt5:theme/openSUSE_Leap_15.2/home:maxrd2:qt5:theme.repo zypper refresh zypper install qtcurve