sync.js

try {
    document.addEventListener('readystatechange', function () {
    try {
        if (document.readyState === 'interactive') {
        let i = 0;
        let Map_ = new Map();
        let Headers_ = new Headers()
        let DOMParser_ = new DOMParser();
        let URLSearchParams_ = new URLSearchParams(location.search);
        Headers_.set('Cache-Control', 'no-cache, no-store, must-revalidate');
        document.addEventListener('scroll', function () {
            try {
                let HTMLformElement_ = document.querySelector('#order-list-filter');
                let FormData_ = new FormData(HTMLformElement_);
                FormData_.set('i', i);
                FormData_.set('section', URLSearchParams_.get('section'));
                FormData_.set('page', i);
                let fetch_ = fetch(location.origin.concat(location.pathname), {
                    method: 'POST',
                    headers: Headers_,
                    body: FormData_
                }).then(function (data) {
                  console.log(data.text());
                  return data;
                });
                Map_.set(i, fetch_);
                for (i; i < Map_.size; i++) {
                    Map_.values().next().value.then(Map_.values().next().value);
                }
            } catch (e) {
                console.log(e);
            }
        });
        }
    } catch (e) {
        console.log(e);
    }
    });
} catch (e) {
    console.log(e);
}