The DMR++ parser doesn't see a newline (cr?) as whitepspace.
The DmrppParserSax2 parser fails to see cr/lf/newline as a white space.
This works: (Note: The single, additional, space at the beginning of the line beginning with xmlns:dmrpp):
And that's probably a bug in the DMR parser too.
I closed this because the issue is outside of the scope of our influence (i.e. libxml2)