Steps to Reproduce
1. Make Caller the first field on the Incident form.
2. Enter a caller into the Caller field and save the incident.
3. Create a UI policy that sets caller to hidden and make it active.
4. Reload a new incident form. Note that Recent selections is visible in the top left of the screen.
As a workaround, set the field to read-only so it does not focus or personalize the Form Layout field. This ensures an editable field is present in the Layout field before the Reporting User field. The field can be hidden as long as it takes the focus first.
Related Problem: PRB608291