Current Problem:
When performing a production-to-sandbox data copy, custom fields that have been deleted in the production environment but are still residing in the "Trash" (not yet permanently deleted after 60 days) are being copied to the Sandbox environment.

There is an active Feature request below

• JRACLOUD-82601 - Trashed custom fields in production are copied as active to the sandbox

 But this is not explained in the below document, so it is not clear why the deleted custom field is copied as active in sandbox.

• https://support.atlassian.com/organization-administration/docs/what-data-is-copied-to-sandboxes/

Suggested Solution:
Add explanation to document that sandbox data copy from production will copy the trashed custom field as active field