https://support.atlassian.com/confluence/kb/cannot-share-a-link-to-this-site-error-in-the-share-a-link-blueprint-in-confluence-server/
'Cannot share a link to this site' error in the Share a link blueprint in Confluence Server |...
Fix 'Cannot share a link to this site' error in Confluence Server by adding URLs to the allowlist. Learn how to resolve it here.
link to this site