public void deselect(String label, boolean withGuardAjax) {
        if (!isSelected(label)) {
            return;
        }

        toggleSelection(label, true, withGuardAjax);
    }
Is the input using AJAX "itemUnselect" event?

@return true if using AJAX for itemUnselect
primefaces-selenium/primefaces-selenium-components/src/main/java/org/primefaces/selenium/component/SelectManyMenu.java