If you are changing a job configuration and you step away... then the system logs you out based on time away... then you come back and apply the changes in the window you have open, the job configuration is blanked.

No change should occur to the job configuration. The button to apply/save should be blocked. 

If you do not have plugins for tracking the job configuration then you have no way to recover that job. Plugins are a remedy to this bug but not a proper solution.