Comment 3 for bug 1658970

Actually, there is a section in the preferences file (created by the preferences skeleton) which defines minimal defaults for a basic document template - IIRC it is used e.g. when importing a foreign vector file format (like PDF), or SVG files without editor metadata for Inkscape:

  <group
     id="template">
    <sodipodi:namedview
       id="base"
       pagecolor="#ffffff"
       bordercolor="#666666"
       borderopacity="1.0"
       objecttolerance="10.0"
       gridtolerance="10.0"
       guidetolerance="10.0"
       inkscape:pageopacity="0.0"
       inkscape:pageshadow="2"
       inkscape:window-width="640"
       inkscape:window-height="480" />
  </group>

https://bazaar.launchpad.net/~inkscape.dev/inkscape/trunk/view/head:/src/preferences-skeleton.h#L61

Possibly this section could be exposed in the preferences.

AFAIU the values in that preferences group do not act as 'fallback' in general for Inkscape SVG files which do not define specific properties for Inkscape (in <namedview/>). The template is used when opening files that do not provide the metadata at all.

TODO: search for older reports specific to this generic (hidden) template (I recall e.g. a request for a configurable template for PDF import).