Para openSUSE Tumbleweed execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/X11:xfce:4.18/openSUSE_Tumbleweed/X11:xfce:4.18.repo
zypper refresh
zypper install xfwm4
Para openSUSE Slowroll execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/X11:xfce:4.18/openSUSE_Slowroll/X11:xfce:4.18.repo
zypper refresh
zypper install xfwm4
Para 15.6 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/X11:xfce:4.18/15.6/X11:xfce:4.18.repo
zypper refresh
zypper install xfwm4
Para 15.5 execute o seguinte como root:
zypper addrepo https://download.opensuse.org/repositories/X11:xfce:4.18/15.5/X11:xfce:4.18.repo
zypper refresh
zypper install xfwm4