For openSUSE Leap 42.3 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/Documentation:Auto/openSUSE_Leap_42.3/Documentation:Auto.repo
zypper refresh
zypper install release-notes-openSUSE
For openSUSE Leap 42.2 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/Documentation:Auto/openSUSE_Leap_42.2/Documentation:Auto.repo
zypper refresh
zypper install release-notes-openSUSE
For openSUSE Leap 42.1 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/Documentation:Auto/openSUSE_Leap_42.1/Documentation:Auto.repo
zypper refresh
zypper install release-notes-openSUSE
For openSUSE Factory run the following as root:
zypper addrepo https://download.opensuse.org/repositories/Documentation:Auto/openSUSE_Factory/Documentation:Auto.repo
zypper refresh
zypper install release-notes-openSUSE