libqt5-qtbase from home:cfeck:branches:KDE:Qt:5.15 project
Select Your Operating System
Add repository and install manually
For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:cfeck:branches:KDE:Qt:5.15/openSUSE_Tumbleweed/home:cfeck:branches:KDE:Qt:5.15.repo zypper refresh zypper install libqt5-qtbase