Smart font optional features for Graphite and OpenType fonts

LibreOffice supports optional font features for the smart font technologies SIL Graphite and OpenType. In LibreOffice, users can access the optional font features by setting extended font names in the fonts dialog. You need to enter IDs from below table after the font name. A user interface for setting the features is implemented in version 6.2.

Examples
For example for the font "Linux Libertine G": or a combination of features:
 * (small caps)
 * (proportional old style numbers)



Please note that most fonts only support a subset of following optional features!

Limitations
Limitations of the current support is that there is no support for optional OpenType features in the OOXML export. Also, the ODF 1.2 standard does not yet provide OpenType optional features support. This feature is scheduled for the standard revision ODF 1.3.

On Graphite fonts
For Graphite fonts, please see following [http://www.numbertext.org/linux/fontfeatures.pdf HowTo for the font features of Linux Libertine G and Linux Biolinum G] and [http://scripts.sil.org/cms/scripts/page.php?site_id=projects&item_id=graphite_fonts SIL Graphite fonts].

Smart fonts bundled with LibreOffice
On Linux, MS Windows and Apple macOS, a large number of smart fonts are installed by the operating system or other applications. Additionally, each LibreOffice installation bundles following smart fonts:

''' Please cross-check whether following fonts lists are correct!! '''


 * Linux Biolinum G
 * Linux Libertine Display G
 * Linux Libertine G
 * Noto Sans
 * Noto Serif
 * Source Code Pro
 * Source Sans Pro
 * Source Serif Pro

Following bundled fonts do not support optional smart font features: Caladea, Carlito, DejaVu Sans, DejaVu Sans Condensed, DejaVu Sans Mono, DejaVu Serif, DejaVu Serif Condensed, Gentium Basic, Gentium Book Basic, Liberation Mono, Liberation Sans, Liberation Sans Narrow, Liberation Serif, Noto font family other than Noto Sans and Noto Serif.

List of optional smart font features and their ID
Note: All Graphite font feature IDs are font specific, depending on which font you are used.