Для 15.6 запустите от имени root:
zypper addrepo https://download.opensuse.org/repositories/home:AlecJY:crostini-test/15.6/home:AlecJY:crostini-test.repo
zypper refresh
zypper install meson
Для 15.5 запустите от имени root:
zypper addrepo https://download.opensuse.org/repositories/home:AlecJY:crostini-test/15.5/home:AlecJY:crostini-test.repo
zypper refresh
zypper install meson
Для 15.4 запустите от имени root:
zypper addrepo https://download.opensuse.org/repositories/home:AlecJY:crostini-test/15.4/home:AlecJY:crostini-test.repo
zypper refresh
zypper install meson