[eliaspro]

The very fundamental problem is just, that the fact that the process/application/service has a PID/displays a window does not equal to the fact, that the service/application is ready to serve requests/the user.

This is why there are protocols like sd_notify [1] or readinessProbe [2] to determine the actual state of the launched service/process/application.

[1] https://www.freedesktop.org/software/systemd/man/254/sd_noti...

[2] https://kubernetes.io/docs/concepts/configuration/liveness-r...