GeoNetwork is a catalog application to manage spatially referenced resources. It provides powerful metadata editing and search functions as well as an interactive web map viewer. It is currently used in numerous Spatial Data Infrastructure initiatives across the world.
The approach to apply templates may not work if the element does not exist (also relevent for other elements)
a for-each approach would be better
suggestion here would be to use xsl:if
on geonetwork 3.10.10 when a iso19139:md_distribution has no description, the schema.org json created is unparsable:
this xml
renders
below case is rendered fine: