GeoNetwork 4.0.5 release is a minor release with some changes:
Harvester / Add visual summary
DOI / Update support and manage existing DOI from editor (see Digital Object Identifier (DOI))
DOI / Schematron validation to make DataCite XSD error reporting more comprehensive
Permalink to editor using a specific view or by UUID
and more … see 4.0.5 issues and
pull requests for full details.