For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:sbradnick/openSUSE_Tumbleweed/home:sbradnick.repo
zypper refresh
zypper install lite-xl
For 15.6 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:sbradnick/15.6/home:sbradnick.repo
zypper refresh
zypper install lite-xl
For 15.5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:sbradnick/15.5/home:sbradnick.repo
zypper refresh
zypper install lite-xl