How is the transfer of values ​​(weight) on the site?

Question

Delivery

Good evening.
Please help me figure out exactly how the value of the weight of goods is transferred to the CDEK delivery calculator on the example of this site https://abekker.ru/
Actually, we add the product to the cart, proceed to checkout on the page https://abekker.ru/cart, and from there we go to the page "Delivery and payment" https://abekker.ru/dostavka-i-oplata, where the calculator from the CDEK delivery service is installed.
The value of the total weight of the purchase is automatically transferred to the "cdek_weight" field.

Here this weight has a value of 1700.
How is this parameter passed?

Answer 1

It is quite obvious that the data is stored on the client in cookies or localStorage.
And when we are on the delivery page, we check -> there is data => we substitute them in the field.
There is also an option that the user ID is stored on the server, and with it the user data. But I don’t think that they began to bother with this / it made sense.
Therefore, I advise you to check your cookies, localstorage. You can also open the source code and look for the js code that is responsible for this. Or the Network tab in chrome will show what requests / scripts are loaded into the browser - you can see there too