How to configure which fields are shown and searched in the To, Cc, and Bcc fields of the email client.

If you need to change which fields are shown or searched on the email reference fields within the email client such as the To field. You can edit a system property "glide.ui.email_client.email_address.disambiguator".

1. Navigate to sys_properties.list
2. Search for "glide.ui.email_client.email_address.disambiguator"
3. Set the fields from sys_user as needed separated by a semi colan. 
4. Save the record.

There is also a property "glide.ui.email_client.email_address.disambiguator_search" Which can be set to false if you only want to show the additional fields but not search them. 

Since Tokyo this configuration has moved to the default Email Client Configuration record.

Please follow Define email client recipient qualifiers to configure this