   Date.prototype.toDateInputValue = (function () {
        let local = new Date(this);
        local.setMinutes(this.getMinutes() - this.getTimezoneOffset());
        return local.toJSON().slice(0, 10);
      });

      // Set parent's deadline as placeholder value for deadline fields
      let rows = document.querySelectorAll('.accordion-row');
      rows.forEach(function (row) {
        let parentDeadline = row.getAttribute('deadline-date');
        let taskList = $('#task-list-' + row.getAttribute('obje