Saxon

A bit more detail of the bug, for the record. In s9api, when the destination of a XsltTransformer is specified as a Serializer, there is some logic to combine the serialization properties requesed in xsl:output declarations in the stylesheet with the properties requested programmatically using the Serializer API. This logic is not being executed in the case where the XsltTransformer is invoked as the destination of another transformation, as distinct from the case where it is invoked directly using the transform() method. The effect is that the serialization properties used are those from the Serializer object, not those from the stylesheet. A workaround is therefore to set the required properties programmatically on the Serializer object.