gtk:widget-font-options (widget)

widget -- a gtk:widget object
options -- a cairo:font-options-t instance, or nil to unset any previously set default font options

The gtk:widget-font-options function returns the font options used for Pango rendering. The (setf gtk:widget-font-options) function sets the font options. When not set, the default font options for the GDK screen will be used. Deprecated since 4.16. Do not use this function in newly written code.