Local storage on checkout page

Question

Where and why checkout-data section from local storage object cleaned after added product to cart?

Before:

{
  "checkout-data": {
    "selectedShippingAddress": null,
    "shippingAddressFromData": {
      "company": "",
      "telephone": "",
      "firstname": "Tetwe",
      "lastname": "twetwet",
      "street": {
        "0": "twetew",
        "1": "",
        "2": ""
      },
      "city": "213123",
      "postcode": "123123",
      "country_id": "DE",
      "region": ""
    },
    "newCustomerShippingAddress": null,
    "selectedShippingRate": null,
    "selectedPaymentMethod": null,
    "selectedBillingAddress": null,
    "billingAddressFromData": null,
    "newCustomerBillingAddress": null,
    "validatedEmailValue": "[email protected]",
    "inputFieldEmailValue": "[email protected]"
  }
}

After added product to cart and reload checkout page:

{
  "checkout-data":{
    "selectedShippingAddress":null,
    "shippingAddressFromData": null,
    "newCustomerShippingAddress":null,
    "selectedShippingRate":null,
    "selectedPaymentMethod":null,
    "selectedBillingAddress":null,
    "billingAddressFromData":null,
    "newCustomerBillingAddress":null
  }
}

Answer 1

Issue was decided at Magento 2.3 https://github.com/magento/magento2/issues/12362