G09 (objectMaterialsTech) not fully backwards compatible
During the implementation of G09,
extentMaterialsTech's type has been changed to
lido:conceptComplexType which doesn't allow for text nodes. Hence the current implementation isn't backwards compatible.
Note: In several context's it is necessary to define a type that accepts mixed content, i.e. text nodes and
conceptComplexType. This issue could be solved when this new type is available.