XNAT 1.8.4.1 Release Notes
XNAT 1.8.4.1 is a hotfix release, addressing a single critical issue (XNAT-7036) that can break the site's handling of the siteConfig object, which then results in a failure to render the Admin UI or Administer Users UI. No other core functionality is affected by this bug or its corresponding fix.
We strongly urge all users of XNAT 1.8.4 to upgrade immediately to this release.
For all other improvements in XNAT 1.8.4, see XNAT 1.8.4 Release Notes.