src/elements/Elt.dom.js
function(elt,_class){
		var oldLength = elt.classList.length;
		elt.classList.remove(_class);
		return oldLength !== elt.classList.length;
	}
function(elt,_class){
		var oldLength = elt.classList.length;
		elt.classList.remove(_class);
		return oldLength !== elt.classList.length;
	}
Overrided in dom.js