After upgrade not working shopping cart.
First when upgrade to 1.7.8 and PHP 7.3 at shopping cart not working ajax update on products quantities and delete not working.
When change to PHP 7.4 error in shopping cart: Notice: Trying to access array offset on value of type null
First issue I think with jquery. Second need check if is set index.
But I don't know where fix it.
Or it is theme problem or core?
I think problem here: cart-detailed-totals.tpl
```
<div class="card-block">
{foreach from=$cart.subtotals item="subtotal"}
{if $subtotal.value && $subtotal.type !== 'tax'}
<div class="cart-summary-line" id="cart-subtotal-{$subtotal.type}">
<span class="label{if 'products' === $subtotal.type} js-subtotal{/if}">
{if 'products' == $subtotal.type}
{$cart.summary_string}
{else}
{$subtotal.label}
{/if}
</span>
<span class="value">{$subtotal.value}</span>
{if $subtotal.type === 'shipping'}
<div><small class="value">{hook h='displayCheckoutSubtotalDetails' subtotal=$subtotal}</small>
</div>
{/if}
</div>
{/if}
{/foreach}
</div>
I tryed to track, but don't know. I think problem in $cart.subtotals that index empty or smth. But don't know where find this area in with controller or class.
Any ideas?
[jquery error][1]
[Cart error 1][2]
[Cart error 2][3]
[Cart error 3][4]
[Cart error 4][5]
[Cart error 5][6]
[1]: https://i.stack.imgur.com/H9vmt.png
[2]: https://i.stack.imgur.com/uGCHF.png
[3]: https://i.stack.imgur.com/jqqLD.png
[4]: https://i.stack.imgur.com/ENahu.png
[5]: https://i.stack.imgur.com/2oLQB.png
[6]: https://i.stack.imgur.com/InO7F.png