The <h8> tag

<h8>

Purpose

Defines a custom paragraph style within a section, preferably to be used as a subheading.

Attributes
Content

When exporting to ODT, novelibre converts this to “Heading 8”.

The xml:lang attribute

The optional locale is for ODF document spell check control.

The attribute has the form <Language code> or <Language code>-<Country code>, where the language code is according to ISO 639-1, and the optional country code is according to ISO 3166-2.

Example: en-GB is for British English.