detect if schedule isn't actually functional and at least warn user (if not try to fix)

[jzacsh]

I'm filing this a feature-request but I could see a valid argument for this being a UX bug.

Is your feature request related to a problem? Please describe.

teejee2008/timeshift#396 - basically that bug was closed with the manual fix (end-user fix this by hand) but I think it would be great if timeshift tried to detect that the schedule it registered with a service that's not actually enabled.

Describe the solution you'd like

timeshift should try to detect that the schedule it registered with a service isn't actually enabled, and tell user how to fix (of course great to fix it via click of a button, but at least indicate something's wrong).

Describe alternatives you've considered

Not filing this bug and hoping people just search the web for "time shift not running" and hit aformentioned report, and fix it themselves.

Additional context

Here's a screenshot of the timeshift UI showing a big confident green checkmark that "schedule snapshots are enabled" when in fact on my system they're not (due to this bug):

[jinzhongjia]

that happend on my arch too

[PVermeer]

Agreed.
The message is misleading. I would not have noticed that it was not running, if I set it to a longer period than hourly on a clean install of Manjaro.
Cron services are initially disabled.

teejee2008/timeshift#396 (comment):

systemctl enable cronie.service
systemctl start cronie.service

[ironhak]

why it does not get enabled by default?

[Nate700]

can this get fixed or warn the user?

[ygerlach]

Maybe timeshift could store the last time it was ran from cron and show that. (and warn if the last time is to old or something)