In LibreOffice Writer version 6.0.5.2 on Ubuntu 16.04, when I try to export ODT to HTML (or save as), I get wrong indentation in lists.
For example, this is what the ODT document looks like:
Exporting it as XHTML results in:
(Notice that indentation outside of lists does work.)
And saving it as HTML preserves indentation but messes line spacing and changes the list bullets:
