Render FontAwesome correctly in Firefox
    
    Based on Mozilla specification
    (https://developer.mozilla.org/en-US/docs/Web/CSS/@font-face#specifying_local_font_alternatives)
    the reference to 'local' should contain either the full path to the
    font location (which we don't want to hard code) or a reference to the font name.
    The latter renders FontAwesome correctly in Firefox for packages
    installed locally.