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data-ajax-cart-section-scroll

If you have a scrollable area within a data-ajax-cart-section section, the scroll position will be reset to top every time when the cart is changed because the section’s HTML will be completely replaced with a new one.

Add the data-ajax-cart-section-scroll attribute to the scrollable area and Liquid Ajax Cart will keep the scroll position unchanged.

 <div data-ajax-cart-section>
  <h2>Cart</h2>

  <div class="my-cart__items" data-ajax-cart-section-scroll>
    
    {% comment %}
        Scrollable area
    {% endcomment %}
    
  </div>

</div> 

If you have several scrollable areas, add the data-ajax-cart-section-scroll attribute with unique parameters so Liquid Ajax Cart can distinguish them after HTML update.

 <div data-ajax-cart-section>
  <h2>Cart</h2>

  <div class="items" data-ajax-cart-section-scroll="main">

    {% for item in cart.items %}
      <div class="line-item" data-ajax-cart-section-scroll="{{ item.key }}">
        {% comment %}
          Despite it sounds crazy, lets imagine that each line-item is scrollable.
          Thus it needs the data-ajax-cart-section-scroll attribute with a unique parameter
        {% endcomment %}
      </div>
    {% endfor %}

  </div>

</div> 

Reference