Hi Glenn,
FAQ Book uses 2 icon sets:
1) The default Joomla icon set: Icomoon
https://docs.joomla.org/J3.x:Joomla_Standard_Icomoon_Fonts
The Icomoon icon set by default is using the class
icon- for the icons:
[class^="icon-"]:before, [class*=" icon-"]:before {
font-family: 'IcoMoon';
2) The FontAwesome icon set:
The FontAwesome icon set by default is using the class 'fa-'.
http://fontawesome.io/examples/
Joomlashack templates are using the class '
icon-' for the Fontawesome icons. This means that they have broken compatibility with the Icomoon icons.
This class is meant to be used by the Icomoon set and should not be used for the Fontawesome icons.
FAQ Book supports the default Joomla classes. This is a problem caused by the Joomlashack template overriding the default classes.