XML doesn't round-trip

[retorquere]

This input:

<?xml version="1.0"?>
<RDF xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#" xmlns:em="http://www.mozilla.org/2004/em-rdf#">

  <Description about="urn:mozilla:install-manifest">
    <em:description>Make Zotero useful for us LaTeX holdouts.</em:description>
    <em:id>better-bibtex@iris-advies.com</em:id>
    <em:name>Zotero Better Bib(La)Tex</em:name>
    <em:version>SOURCE</em:version>
    <em:homepageURL>https://github.com/retorquere/zotero-better-bibtex/wiki</em:homepageURL>
    <em:creator>Emiliano Heyns</em:creator>
    <em:iconURL>chrome://zotero-better-bibtex/skin/better-bibtex.svg</em:iconURL>
    <em:updateURL>https://retorquere.github.io/zotero-better-bibtex/update.rdf</em:updateURL>
    <em:type>2</em:type> <!-- type=extension -->
    <em:optionsURL>chrome://zotero/content/preferences/preferences.xul#better-bibtex</em:optionsURL>

    <!-- Requires Firefox or Zotero Standalone -->
    <em:targetApplication>
      <Description>
        <em:id>zotero@chnm.gmu.edu</em:id>
        <em:minVersion>5.0</em:minVersion>
        <em:maxVersion>5.0.*</em:maxVersion>
      </Description>
    </em:targetApplication>
    <em:targetApplication>
      <Description>
        <em:id>juris-m@juris-m.github.io</em:id>
        <em:minVersion>5.0</em:minVersion>
        <em:maxVersion>5.0.*</em:maxVersion>
      </Description>
    </em:targetApplication>
  </Description>
</RDF>

when put through stringToJs/jsToString outputs

<RDF 
  xmlns="http://www.w3.org/1999/02/22-rdf-syntax-ns#" 
  xmlns:em="http://www.mozilla.org/2004/em-rdf#">
  <Description about="urn:mozilla:install-manifest">
    <em:description 
      xmlns:em="http://www.w3.org/1999/02/22-rdf-syntax-ns#">Make Zotero useful for us LaTeX holdouts.
    </em:description>
    <em:id>better-bibtex@iris-advies.com</em:id>
    <em:name>Zotero Better Bib(La)Tex</em:name>
    <em:version>5.0.0</em:version>
    <em:homepageURL>https://github.com/retorquere/zotero-better-bibtex/wiki</em:homepageURL>
    <em:creator>Emiliano Heyns</em:creator>
    <em:iconURL>chrome://zotero-better-bibtex/skin/better-bibtex.svg</em:iconURL>
    <em:updateURL>https://retorquere.github.io/zotero-better-bibtex/update.rdf</em:updateURL>
    <em:type>2</em:type>
    <em:optionsURL>chrome://zotero/content/preferences/preferences.xul#better-bibtex</em:optionsURL>
    <em:targetApplication>
      <Description>
        <em:id>zotero@chnm.gmu.edu</em:id>
        <em:minVersion>5.0</em:minVersion>
        <em:maxVersion>5.0.*</em:maxVersion>
      </Description>
    </em:targetApplication>
    <em:targetApplication>
      <Description>
        <em:id>juris-m@juris-m.github.io</em:id>
        <em:minVersion>5.0</em:minVersion>
        <em:maxVersion>5.0.*</em:maxVersion>
      </Description>
    </em:targetApplication>
  </Description>
</RDF>

notice the extra namespace declaration on em:description