Enpass 6.0 and SilverBlue

Has anyone managed to install Enpass 6.0 with SilverBlue. It looks like they removed the installer in favor of providing an RPM. That RPM wants to write to /opt though so I run into the issue documented here: Determine support path for RPMs that install into `/opt`, `/usr/local` etc · Issue #233 · coreos/rpm-ostree · GitHub

Will also try and ask at https://discussion.enpass.io.