Hi, 
Hope you'r well !

I know it's a specific question and that fonctionnality isn't added by default but I add a sticky add to cart button on my product pages on mobile.

It's working good but the only problem is that is opening the cart page instant of the side cart and I don't found the way to just open the side cart.

Here is my custom.js code 

$(document).ready(function () {
  var addToCartDiv = $("#fixed-add-to-cart-div");
  var addToCartButton = $("#fixed-add-to-cart-button");
  var addToCartForm = addToCartButton.closest("form");
  var addToCartButton = $("#fixed-add-to-cart-button");
  var productAvailability = $product.quantity > 0;
  $(window).scroll(function () {
    var windowHeight = $(window).height();
    var documentHeight = $(document).height();
    var scrollPercentage =
      $(window).scrollTop() / (documentHeight - windowHeight);
    if (scrollPercentage > 0.25) {
      addToCartDiv.addClass("fixed-add-to-cart-div-visible");
    } else {
      addToCartDiv
        .removeClass("fixed-add-to-cart-div-visible slide-in-up")
        .addClass("slide-out-down");
    }
  });
  if (productAvailability) {
    addToCartButton.prop("disabled", false);
  } else {
    addToCartButton.prop("disabled", true);
  }
  $("#fixed-add-to-cart-div").click(function () {
    addToCartForm.submit();
    $("#canvas-mini-cart").trigger("click");
  });
});

Could you please just help me to found the good syntahx to open the cart on side ? 

(If you want to check the website I need you to give my your IP adress to get access)

Have a nice day !

Raphaël