So there is an order form on the site with a large number of fields (already optimized and still the number is quite large).
Task: When the user is bored with filling in the data, he clicks a cross or closes the browser - save all his entered form data somewhere (in a session using PHP, and it looks like this is the only available option).
Purpose: After some time has passed, the user returns to the site, opens the form, and the form is almost full with the data that he did not fill out last time, thereby speeding up the entire process of ordering products.
Features: The form works by means of JQuery and is sent to the AJAX server by request, and, accordingly, the order is thereby completed. The browser does not cache such forms, and after reloading the page again you have to fill out.