dbus-launch is probably not needed in systemd environment

[Vladimir-csp]

I do not have dbus-launch in my system (part of dbus-x11 package which is not installed).
From emptty log:

2024/06/08 12:06:10 Starting dbus-launch
2024/06/08 12:06:10 Could not find command 'dbus-launch' on PATH
2024/06/08 12:06:10 No output from dbus-launch

Dumping env via ~/.config/emptty script shows that it already contains DBUS_SESSION_BUS_ADDRESS=unix:path=/run/user/1000/bus, which was probably set by systemd-related pam modules.

Perhaps it would be prudent to not even try to run dbus-launch if this var is already set.

[tvrzna]

It should not start, if ALWAYS_DBUS_LAUNCH is not set to true and by default it is set to false. So first step is to fix the bug that ignores config and second is to check a value of DBUS_SESSION_BUS_ADDRESS env.