As you can see, i am explicitly setting standalone to undef which, according to the docs, is suppose to prevent the attribute from being printed in the declaration.

I don't see anywhere in the docs that say standalone is a constructor option.

If a dtd was set in the constructor, the standalone attribute of the declaration will be set to 'no' and the doctype declaration will be appended to the XML declartion, otherwise the standalone attribute will be set to 'yes'. This can be overridden by providing a 'standalone' key in @args. If you do not want the standalone attribute to show up, explicitly provide undef as the value.

So just add the doctype 

use XML::Generator qw( );
my $gen = XML::Generator->new(
   conformance => 'strict',
   encoding    => 'UTF-8',
   dtd         => [ 'html', 'PUBLIC', $xhtml_w3c, $xhtml_dtd ],
);
print $gen->xml(
   $gen->html('...')
);

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In reply to Re: Getting XML::Generator to DWIW with the XML declaration by ikegami
in thread Getting XML::Generator to DWIW with the XML declaration by jeffa

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