Am 15.08.2020 um 08:46 schrieb Wolfhart Totschnig
wolfhart.totschnig@xxxxxxxxxxx:

Dear Gerrit,

Thank you for the explanation! I understand now why I get the @xmlns
attribute with Dimitre's solution. But I still don't understand why I
also get it with Graydon's solution, which does not use <xsl:copy> but
serialize() followed by parse-xml-fragment(). In the input data, the
@xmlns attribute is not on the <i> element itself but on an ancestor
element several levels up. Why then does it show up in the result of
serialize()? And how do I get rid of it using Graydon's approach?

Neither serialization nor parsing loses any namespaces present in the
input tree so while your input markup might have a namespace declaration
high up in the tree each node in the tree carries its namespace
information and if you have serialize and parse the namespace
information is preserved.

<xsl:template match="*" mode="strip-namespace">
  <xsl:element name="local-name()">
     <xsl:apply-templates select="@* | node()" mode="#current"/>
  </xsl:element>
</xsl:template>

<xsl:apply-templates select="serialize(node()) => substring-before(':')
=> lower-case() => parse-xml-fragment()" mode="strip-namespace"/>

If that doesn't work you might want to summarize which input you have
and how your current XSLT based on Graydon's suggestion looks, plus the
result you want and the one you get.