in log4j2-ecs-layout/src/main/java/co/elastic/logging/log4j2/EcsLayout.java [239:247]
private void serializeMarker(StringBuilder builder, Marker marker) {
EcsJsonSerializer.serializeSingleTag(builder, marker.getName());
if (marker.hasParents()) {
Marker[] parents = marker.getParents();
for (int i = 0; i < parents.length; i++) {
serializeMarker(builder, parents[i]);
}
}
}