`libxml-parse-xml-region` strips out the namespace information, and namespace prefix in the DOM representation.

Stripping out the NAMESPACE information is a bug.

FWIW, the XML file under question is a OpenDocument styles file.

See the attached =xml.org= file for more information.  That is, ...execute the org babel blocks, and follow the inline comments in there. 


In GNU Emacs 29.0.50 (build 3, x86_64-pc-linux-gnu, GTK+ Version
 3.24.34, cairo version 1.16.0) of 2022-11-19 built on debian
Repository revision: a6ae13af42ede6618c326855ea4c95e0298fb75b
Repository branch: master
Windowing system distributor 'The X.Org Foundation', version 11.0.12101004
System Description: Debian GNU/Linux bookworm/sid

Configured using:
 'configure --with-imagemagick --with-xwidgets --with-json
 --without-compress-install'

Configured features:
ACL CAIRO DBUS FREETYPE GIF GLIB GMP GNUTLS GPM GSETTINGS HARFBUZZ
IMAGEMAGICK JPEG JSON LCMS2 LIBOTF LIBSELINUX LIBSYSTEMD LIBXML2
M17N_FLT MODULES NOTIFY INOTIFY PDUMPER PNG RSVG SECCOMP SOUND SQLITE3
THREADS TIFF TOOLKIT_SCROLL_BARS X11 XDBE XIM XINPUT2 XPM XWIDGETS GTK3
ZLIB