If this policy is set to a blank string or not configured, Google Chrome OS will not show an autocomplete option during user sign-in flow.
If this policy is set to a string representing a domain name, Google Chrome OS will show an autocomplete option during user sign-in allowing the user to type in only their user name without the domain name extension. The user will be able to overwrite this domain name extension.
If the value of the policy is not a valid domain, the policy will not be applied.
Example value: students.school.edu