How disable focus in form.

You can use "autofocus: false" to disable autofocus or use "focus: 'anotherField'" to autofocus a selected field.

const form = [
  {name: "Start", id: "start", type: "datetime"},
  {name: "End", id: "end", type: "datetime"},
];

const data = {
  start: "2023-11-01T10:00:00",
  end: "2023-11-02T12:00:00",
};

const modal = await DayPilot.Modal.form(form, data, {autofocus: false});

See also:
https://api.daypilot.org/daypilot-modal-autofocus/
https://api.daypilot.org/daypilot-modal-focus/