This option specifies a list of terms allowed to be displayed in faceted navigation values.
This parameter is suffixed with the facet name to apply the white list to. The format is:
The value is a comma separated list of terms. Only the term from this list will be displayed as values for the given facet. The matches are case-insensitive.
Only allow "Sydney" and "Melbourne" for the "Location" facet:
Because the list is comma-separated, whitelisting values that contain comma is not possible. To whitelist faceted navigation categories creating commas, a custom plugin is required.