<preserveSpace elements =
list of XPath (subset)/>
Specifies which elements are whitespace-preserving.
Using standard attribute
xml:space with default value
preserve is still the preferred way of specifying this. However, this is not always possible, for example in the case of DTDs/ W3C XML schema that you don't control or in the case of RELAX NG schema which do not really support the concept of attribute default value.
<cfg:preserveSpace xmlns="" elements="address funcsynopsisinfo classsynopsisinfo literallayout programlisting screen synopsis" />