This default mode for combining children DOMs during merge means that where element names match, the process will
try to merge the element data, rather than putting the dominant and recessive elements (which share the same
element name) as siblings in the resulting DOM.
This default mode for combining a DOM node during merge means that where element names match, the process will
try to merge the element attributes and values, rather than overriding the recessive element completely with the
dominant one.