For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/openSUSE:infrastructure:jitsi/openSUSE_Tumbleweed/openSUSE:infrastructure:jitsi.repo
zypper refresh
zypper install yarn
For 15.6 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/openSUSE:infrastructure:jitsi/15.6/openSUSE:infrastructure:jitsi.repo
zypper refresh
zypper install yarn
For 15.5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/openSUSE:infrastructure:jitsi/15.5/openSUSE:infrastructure:jitsi.repo
zypper refresh
zypper install yarn