FWIW, upstream seem to have an intent to resolve this,
https://github.com/xen0vas/UserManager/issues/16:
Application usage from users with limited privileges
- Implement setuid access with privilege control
xen0vas commented on Jun 27, 2020
Application usage from users with limited privileges in order to be
able to
use UserManager for changing passwords and have limited access. The
implementation includes setuid setgid privilege checks as well as
dropping
and restoring privileges as needed due to elevated functionality
when
changing passwords and accessing system files.
Gürkan, maybe you could work with them to deal with this prior to
packaging?