mkvtoolnix-gui from home:aschnell:boost2 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:aschnell:boost2/openSUSE_Tumbleweed/home:aschnell:boost2.repo zypper refresh zypper install mkvtoolnix-gui