After a Jira Cloud-to-Cloud Migration we see Preview unavailable for attachments but they were migrated

Issue Summary

Attachments preview not available in Jira Issues on migrated projects.
Attachments were migrated - their preview is failing to load.

Steps to Reproduce

1. Migrate projects using Jira C2C Beta Tool
2. View Jira Issues in the cloud site which have attachments 
3. The attachments are always accessible in the Jira Issue and were migrated successfully - this affects only the attachment preview

Expected Results

• The attachment preview feature works as expected

Actual Results

• The attachment preview doesn't display automatically but shows a Preview unavailable error message

Workaround

Contact the Cloud Migrations Support team via a support ticket.