For openSUSE Slowroll run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:illuusio:nodejs-packages/openSUSE_Slowroll/home:illuusio:nodejs-packages.repo
zypper refresh
zypper install icu
For 16.0 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:illuusio:nodejs-packages/16.0/home:illuusio:nodejs-packages.repo
zypper refresh
zypper install icu
For 15.6 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:illuusio:nodejs-packages/15.6/home:illuusio:nodejs-packages.repo
zypper refresh
zypper install icu