Office cannot import splitted document with numbering

Reproducible on demo XWiki Jetty/HSQLDB 17.10.3 with LibreOffice 25.8.4.2 with sample on this ticket.

However, if I create from scratch odt or doc, docx in LibreOffice with numbered headings level 1, level 2 and level 3 with lorem (type lorem and press F3 to generate dummy text) content.

When importing this document into XWiki and selecting split pages by Heading 1 & 2 & 3, the result is:

• A parent wiki page titled Test 3, containing:
  • two internal links of the page pointing to the child pages 1One and 2Next (both derived from Heading 1).
• First two child pages:
  • 1One and 2Next, each containing the content that follows its respective Heading 1 and in the end page 1One has internal links pointing to sub-pages 1.1Two and 1.2Three. Page 2Next has content and link to sub-page 2.1Next
• Next sub-child pages:
  • 1.1Two and 1.2Three respective Heading 2 has their content
  • {2.1Next}} respective Heading 2 has content with internal link to 2.1Sub next - Heading 2, that page has link to last sub-page 2.1.1Ending - Heading 3

I'd say behavior of splitting is expected if Document is created in LibreOffice and OnlyOffice (I've not tested I don't have it locally) since XWiki listens to such servers. And either it's issue specific to how LibreOffice converts/parses MicrosoftOffice document during importing to XWiki or this limitation of usage XWiki with office files specificly created in MicrosoftOffice or Office365.