Our standard cart that appears as an overlay "inside" your own page will only work that way if you use the complete, ready-made HTML code we provide for your cart buttons in your E-junkie Seller Admin, and you must have at least one complete block of your View Cart code on every page that has any number of Add to Carts.
If you are stripping down the button code to just the bare href= URL alone, perhaps to use that in a plaintext email or in a link-maker widget on a site where you are not allowed to paste HTML, then that would lack the code necessary to make the overlay-style cart work, so in this case the cart button/link would work like a normal link, displaying the cart as a regular page by itself.
If you at least want these basic cart button/links to open a new window/tab, your link-maker widget may have some way to specify a "target" name. Just give the same target name to all your cart-button links to have them open a new window/tab for the cart and keep reusing that separate window/tab for subsequent cart views.
