handle_class: resize does not work if multiple classes are added

[kevinch1]

I'm trying to use a fontawesome class as handle_class, this classes have the format fas fa-[some-name] and it seems that breaks the resizing, I believe it has something to do with the fact that a class with the same name of the one you specify as handle_class + -both is added to the span, and in this case what is doing is generating is a span with this class attribute fas fa-expand-arrows-alt fas fa-expand-arrows-alt-both