Update Custom Field when status changes

[AndreasMoe]

Hi, is it possible to automatically update a custom field when the status changes for a device?
Would like a custom field (now called "turned of since") to set date is status is changed from "Running" to "Stopped"

Users manually update Device status when stopping a server and would like a custom field to be updated when Device status changes from Running to Stopped so that users dont need to search in change log

Can for example a webhook be used? If so, any example code would be very helpfull

Regards