For openSUSE Tumbleweed run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:medozas74/openSUSE_Tumbleweed/home:medozas74.repo
zypper refresh
zypper install simplescreenrecorder
For 15.6 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:medozas74/15.6/home:medozas74.repo
zypper refresh
zypper install simplescreenrecorder
For 15.5 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:medozas74/15.5/home:medozas74.repo
zypper refresh
zypper install simplescreenrecorder
For 15.4 run the following as root:
zypper addrepo https://download.opensuse.org/repositories/home:medozas74/15.4/home:medozas74.repo
zypper refresh
zypper install simplescreenrecorder