[niko42]

Events.prototype.addBasket = function(){
    $('.basket_bottom').on('click', function () {
        this.modal.block(this, '<div class="modal add_basket border_f99100 borderRadius_5">Товар добавлен <a href="/Basket">в корзину</a></div>');
    }.bind(this)); // тут вся соль
};

Uncaught TypeError: Cannot read property 'createDocumentFragment' of undefined

Events.prototype.addBasket = function(){
    $('.basket_bottom').on('click', () => {
        this.modal.block(this, '<div class="modal add_basket border_f99100 borderRadius_5">Товар добавлен <a href="/Basket">в корзину</a></div>');
    });
};

Uncaught SyntaxError: Unexpected token )