I don’t think it’s a bug, is it? I encountered something similar, see for example Putting XML::Twig to the test. I did some performance tests with XML::Twig using different approaches and also ran into similar things. Normally I blame my code.

As is said in the online tutorial:
Note: as of XML::Twig 3.23, there is no longer any need to call flush one last time after the document is completely parsed. If the document was flushed, then it will be "auto-flushed" (to the same filehandle used for the first flush) after the parse.

Maybe the man can shine his light on this one?

cheers
dHarry