How do I change the input attributes of a text field using GreaseMonkey/TamperMonkey?

Question

How do I remove the readonly attribute from this input field?

<input class=" calendar_field" id="zoom_meeting_room[scheduled_on]" name="zoom_meeting_room[scheduled_on]" readonly="readonly" type="text" value="2020-11-07 12:08">

Thank you

Answer 1

Here is an example:

document.querySelector('#zoom_meeting_room[scheduled_on]').removeAttribute('readonly');

or

document.getElementById('zoom_meeting_room[scheduled_on]').removeAttribute('readonly');

In order to avoid errors

const input = document.getElementById('zoom_meeting_room[scheduled_on]');
if (input) { input.removeAttribute('readonly'); }

or

const input = document.getElementById('zoom_meeting_room[scheduled_on]');
input && input.removeAttribute('readonly');

You can also set it to false

const input = document.getElementById('zoom_meeting_room[scheduled_on]');
if (input) { input.readOnly = false; }

or

const input = document.getElementById('zoom_meeting_room[scheduled_on]');
if (input) { input.setAttribute('readonly', false); }