Following documentation, the following XML code added as an XML Extension in Studio does not always make them disappear (the virtual navs) even after restarting the server
<extension target="org.nuxeo.ecm.webapp.directory.DirectoryTreeService" point="trees"> <directoryTree name="bySubjectsNavigation" label="base.navigation.subjects" contentView="bySubjectsContentView" field="subjects" schema="querynav" enabled="false" outcome="subjects_virtual_navigation"> <directory>topic</directory> <directory>subtopic</directory> </directoryTree> <directoryTree name="byCoverageNavigation" label="base.navigation.subjects" contentView="bySubjectsContentView" field="subjects" schema="querynav" enabled="false" outcome="subjects_virtual_navigation"> <directory>topic</directory> <directory>subtopic</directory> </directoryTree> </extension>