We also put features like resizeable bootstrap column with drag & drop (col-md-X), link manager, media manager, special fields edition (e.g. prices with currencies)... Playing with building blocks look more sleek in Odoo version.
It implements: SSL, PDF, Export, same preview than print but no local storage. In the other hand, it has: online payments, auto generation (subscriptions), send by email or regular mail, etc.
It's not a standaline jquery lib but can easily be extracted from the code of Odoo as it's open source.
We worked a ot on the usability to make it smooth to handle images, backgrounds, specific properties of building blocks (e.g. banners, parallax, ...)