private static ListCell<String> getListCell () {
         return new ListCell<>() {
            @Override protected void updateItem (String family, boolean empty) {
               super.updateItem( family, empty );
               if (empty || family == null) { setText( null ); setFont( Font.getDefault() ); }
               else { setText( family ); setFont( Font.font( family, 12 ) ); }
            }
         };
      }

Pretty much all the errors are like this :
javafx.scene.CssStyleHelper calculateValue
WARNING: Caught 'java.lang.ClassCastException' while converting value for '-fx-background-color' from rule '*.list-view *.list-cell' in stylesheet jar:file:/[...]/atlantafx-base-2.1.0.jar!/atlantafx/base/theme/primer-dark.bss

javafx.scene.CssStyleHelper calculateValue
WARNING: Could not resolve '-color-cell-fg' while resolving lookups for '-fx-text-fill' from rule '*.list-view *.list-cell' in stylesheet jar:file:/[...]/atlantafx-base-2.1.0.jar!/atlantafx/base/theme/primer-dark.bss