How to make that an extended attribute field to required?

Go to [Settings > Extended Attributes > Items], choose the extended field and click edit, and you can make the field as a required.

來源連結：

https://support.vitalyun.com/en/vital-crm/faq?view=article&id=5179:how-to-make-that-an-extended-attribute-field-to-required&catid=28

Go to [Settings > Extended Attributes > Items], choose the extended field and click edit, and you can make the field as a required.