Uncaught SyntaxError: Unexpected end of JSON input
    at JSON.parse (<anonymous>)
    at xhr.onload (settings.php:169:37)

function get_general() {
            let site_title = document.getElementById('site_title');
            let site_about = document.getElementById('site_about');

            let shutdown_toogle = document.getElementById('shutdown-toogle');

            let xhr = new XMLHttpRequest();
            xhr.open("GET", "ajax/settings_crud.php", true);
            xhr.setRequestHeader('Content-Type', 'application/x-www-form-urlencoded');

            xhr.onload = function() {
                general_data = JSON.parse(this.responseText);

                site_title.innerText = general_data.site_title;
                site_about.innerHTML = general_data.site_about;

                site_title_inp.value = general_data.site_title;
                site_about_inp.value = general_data.site_about;

                if (general_data.shutdown == 0) {
                    shutdown_toogle.checked = false;
                    shutdown_toogle.value = 0;
                } else {
                    shutdown_toogle.checked = true;
                    shutdown_toogle.value = 1;
                }
            }

            xhr.send('get_general');
        }