Getting "managed object model" error at startup

Hi all --

My iMac, running the new High Sierra 10.13.4 update, has starting throwing a "The managed object model version used to open the persistent store is incompatible with the one that was used to create the persistent store” at startup, showing the dialog below.

Unfortunately the error message doesn’t indicate which application caused it, so I’m having a hard time debugging this problem. The best explanation I’ve found is here.However that page is 10+ years old now, and it sort of assumes you know what application is triggering the error, which I don’t. I have been able to confirm two things:

1. The error doesn’t occur when I do shift-key safe boot startup.
2. The error occurs even after I’ve removed all the items

Based on this I assume it is triggered by a startup process that is not core to the OS (since doesn’t run during safe boot) but is somehow hidden / a daemon that I can’t easily access from the UI. I have no problem working at the bash shell and have LingonX which I can use to identify and manipulate cron-like processes.

Based on the above, I have three questions:

1. Has anyone seen this error and overcome it, and if so, how?
2. If not, does anyone recognize the icon in the alert dialog (yellow triangle with red badge)? That might help pinpoint the app.
3. If not, does anyone have suggestions on how to identify the application or process that might be causing this error?

Thanks in advance for your time & help.

Ramon