Copy and put this to an .xcd file, e.g. DefaultOOXML.xcd
:
<?xml version="1.0"?>
<oor:data xmlns:xs="http://www.w3.org/2001/XMLSchema" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xmlns:oor="http://openoffice.org/2001/registry">
<dependency file="main" />
<oor:component-data xmlns:install="http://openoffice.org/2004/installation" oor:name="Setup" oor:package="org.openoffice">
<node oor:name="Office">
<node oor:name="Factories">
<node oor:name="com.sun.star.text.TextDocument">
<prop oor:name="ooSetupFactoryDefaultFilter" oor:op="fuse" oor:finalized="true">
<value>MS Word 2007 XML</value>
</prop>
</node>
<node oor:name="com.sun.star.sheet.SpreadsheetDocument">
<prop oor:name="ooSetupFactoryDefaultFilter" oor:op="fuse" oor:finalized="true">
<value>Calc MS Excel 2007 XML</value>
</prop>
</node>
<node oor:name="com.sun.star.presentation.PresentationDocument">
<prop oor:name="ooSetupFactoryDefaultFilter" oor:op="fuse" oor:finalized="true">
<value>Impress MS PowerPoint 2007 XML</value>
</prop>
</node>
</node>
</node>
</oor:component-data>
</oor:data>
Put the document to the LibreOffice installation’s share/registry
directory.
And honestly: better don’t do that.