Currently waybar _can_ try to start even if there's no graphical session (and
no sway) running. Adding `Requisite=` prevents this. From `systemd.unit(5)`:
Requisite=
Similar to Requires=. However, if the units listed here are not
started already, they will not be started and the starting of
this unit will fail immediately. Requisite= does not imply an
ordering dependency, even if both units are started in the same
transaction. Hence this setting should usually be combined with
After=, to ensure this unit is not started before the other
unit.
When Requisite=b.service is used on a.service, this dependency
will show as RequisiteOf=a.service in property listing of
b.service. RequisiteOf= dependency cannot be specified directly.
The current service doesn't play too nice with Sway when it is started
from [sway service](https://github.com/xdbob/sway-services).
Waybar is started before the system has a display.
```
Nov 30 22:11:23 ansan waybar[1352]: Unable to init server: Could not
connect: Connection refused
Nov 30 22:11:23 ansan waybar[1352]: cannot open display:
Nov 30 22:11:23 ansan systemd[1306]: waybar.service: Main process
exited, code=exited, status=1/FAILURE
Nov 30 22:11:23 ansan systemd[1306]: waybar.service: Failed with result
'exit-code'.
```
Restarting the service after the system has been initialized works nicely,
so this restart rule should do the trick without tinkering with the
target.
Hugo Osvaldo Barrera
Jeremy Attali
Maxim Baz
Дамјан Георгиевски
Alex