To give project admins the flexibility to manage their own issue security requirements, system admins can also enable project-level settings.
System admin guide
From the top navigation bar, open Apps > Secure Custom Fields, then click on Configure secure custom fields
You can enable project-level configuration option for each secure field.
Project admin guide
From the Project settings, open Apps > Secure Custom Fields
If the custom field has the appropriate context applied (global or project-specific), you’ll see it from the secure field list here.
However, you can only configure permission settings if the system admin has enabled the option for it