Confluence backup and Restore page shows users can import backup from older versions

In Confluence Backup and Restore page, under Upload and restore a site/space backup, it shows following:

This site accepts full site imports from Confluence 4.0 and later, and space imports from Confluence 5.3 and later.

According to this documents, Space backups are incompatible between major versions. Hence, we may need to remove or edit this information in Confluence admin panel.