Activating direct download causes 403 error on file preview

Using the Nuxeo Azure test account and test container, configured according to documentation / test scenario.

• Create a file with attachment in Nuxeo
  => Attachment preview is visible in Nuxeo
  => Binaries accessible from Azure portal
• Restart Nuxeo with direct download activated in nuxeo.conf
  => Attachment preview is not visible in Nuxeo
  => Request is sent but returns a 403 Authentication error.