Inconsistent double adding of products and products lingering after removal


When adding an item to a cart, sometimes the item will be added twice. This also occurs often after having removed an item from the cart and the removed item will not be visible in the cart until the checkout page.

For example, an item will be added, then removed, and then another item will be added, but the total cost of the cart will be the first item’s price, and then two of the second’s, even though only one purchase of the second item is present in the cart. The checkout page seems to reflect this weird behavior but the modal doesn’t

Here is a video of the behavior

Let me know if I can provide any other information. Thank you so much for your help in advance.