Question about openvpn systemd unit file

We use the openvpn packages for Debian bookworm from https://build.openvpn.net/debian/openvpn/. As we ran in #449 with 2.6.7 (thanks @patcable for reporting) we noticed that in the systemd unit file for openvpn KillMode ist set to 'process' and not 'control-group'. Therefore after every segfault there were zombies left and when MaxTasks was reached (which is set to 10) the openvpn service could not start again. That's why the segfault behaviour led to a complete openvpn service outage for us.

My question is: what is the reason that KillMode is set to 'process' here? systemd manual page is saying: "Note that it is not recommended to set KillMode= to process or even none, as this allows processes to escape the service manager's lifecycle and resource management, and to remain running even while their service is considered stopped and is assumed to not consume any resources."

Thanks in advance for your explanation.

Start by locating the Debian package's systemd unit file and reviewing its KillMode setting alongside the systemd documentation. Confirm how the current setting behaves after an OpenVPN segfault and determine whether the issue should document the rationale or change the unit so the reported zombie and restart behavior is addressed.